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Changing the code of life

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Changing the code of life

Congratulations!

On 7 October, the Royal Swedish Academy of Sciences announced that it had awarded the 2020 Nobel Prize for Chemistry to two women scientists: Emmanuelle Charpentier (L), a French microbiologist, geneticist and biochemist, who is now the director of the Max Planck Unit for the Science of Pathogens in Berlin, Germany, and Jennifer Doudna (R), an American biochemist who is a professor of chemistry, biochemistry and molecular biology at UC Berkeley.

The scientists developed a simple, cheap, yet powerful, and precise technique for editing DNA, which is called CRISPR-Cas9 (an acronym for Clustered Regularly Interspaced Short Palindromic Repeats) and popularly referred to as a pair of ‘genetic-scissors’. The technology endows science and scientists with extraordinary powers to manipulate genes to cure genetic diseases, improve crops to withstand drought, mould and pests, and affect climate change, and is considered to be the most important discovery in the history of biology. The Nobel citation refers to Charpentier’s and Doudna’s scientific contribution as a, “tool for rewriting the code of life”, which has “a revolutionary impact on the life sciences, by contributing to new cancer therapies and may make the dream of curing inherited diseases come true”.

For more than four years HealthPad has been following and publishing Commentaries on the scientists’ work. Our Commentaries have a large and growing global following of leading physicians, scientists, policy makers, journalists and students. The Commentaries listed below about CRISPR techniques, which we re-publish to celebrate Charpentier’s and Doudna’s Nobel Prize, have had more than 120,000 views.

Gene editing positioned to revolutionise medicine
1 Feb 2017

Gene editing battles
15 Mar 2017

Who should lead MedTech?
18 Jul 18

Base-editing next-generation genome editor with delivery challenges
17 oct 2018

CRISPR-Cas9 genome editing a 2-edged sword
31 Oct 2018

Will China become a world leader in health life sciences and usurp the US?
27 Feb 2019

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For better or worse we all now live in CRISPR’s world

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Prime editing devised by researchers at the Broad Institute led by David Liu is a significant advance of the original CRISPR gene editing tool discovered in 2012
CRISPR can cut and edit your DNA to correct defects inside your body’s cells to prevent and heal a range of incurable diseases and has revolutionized biomedicine
The original CRISPR is fraught with inaccuracies referred to as off target effects
Prime editing substantially reduces CRISPR’s off target effects and has the potential to correct up to 89% of known disease-causing genetic variations
CRISPR also has the capacity to edit genes in an embryo in such a way that the change is heritable
In 2018 Chinese researcher He Jiankui “created” the world’s first CRISPR babies
This triggered international criticism from scientists and bioethicists
A principal concern is that CRISPR is easy-to-use, cheap, regularly used in thousands of laboratories throughout the world and there is no internationally agreed and enforceable regulatory framework for its use

For better or worse we all now live in CRISPR’s world

In 2012 the world of biomedicine changed when a revolutionary gene editing technology known as CRISPR-Cas9 (an acronym for Clustered Regularly Interspaced Short Palindromic Repeats) was discovered. The technology harnesses your body’s naturally occurring immune system that bacteria use to fight-off viruses and has the potential to forever change the fundamental nature of humanity. Since its discovery CRISPR has been developing at lightning speed primarily because it is simple and affordable and today is used in thousands of laboratories throughout the world.

In this Commentary

In this Commentary we describe prime editing, which is the latest advance of the CRISPR's tool box, devised bya team of researchers, led by Andrew Anzalone, a Jane Coffin Childs postdoctoral fellow from the Broad Institute of MIT and Harvard and published in the October 2019 edition of Nature. Prime editing is significant because it provides a means to eliminate the unintentional consequences of CRISPR and therefore bring the technique closer for use in clinics. But this is still a long way off.

We also review a case where an ambitious scientist “created” the first CRISPR babies. This immediately triggered international criticism and a call for tighter regulatory control of the technology. Scientists and bioethicists are concerned that CRISPR can easily be used to create heritable DNA changes, which ultimately could lead to ‘designer babies’.

These two accounts of CRISPR might seem “opposites” and not sit well together in a single Commentary. Notwithstanding, what prompted putting them together was John Travis, the News Managing Editor of the well-known scientific journal Science, who soon after CRISPR’s discovery in 2012 said, “For better or worse we all now live in CRISPR’s world”.

CRISPR and your DNA

CRISPR is different to traditional gene therapy, which uses viruses to insert new genes into cells to try and treat diseases and has caused some safety challenges. CRISPR, which avoids the use of viruses, was conceived in 2007 when a yogurt company identified an unexpected defence mechanism that its bacteria used to fight off viruses. Subsequent research made a surprising observation that bacteria could remember viruses. CRISPR has been likened to a pair of microscopic scissors that can cut and edit your DNA to correct defects inside your body’s cells to prevent and heal a range of intractable diseases. The standard picture of DNA is a double helix, which looks similar to a ladder that has been twisted. The steps in this twisted ladder are DNA base pairs. The fundamental building blocks of DNA are the four bases adenine (A), cytosine (C), guanine (G) and thymine (T). They are commonly known by their respective letters, A, C, G and T. Three billion of these letters form the complete manual for building and maintaining your body, but tiny errors can cause disease. For example, a mutation that turned one specific A into a T results in the most common form of sickle cell disease.

The original CRISPR

The original CRISPR tool, which is the first and most popular gene editing system, uses a guide RNA (principally a messenger carrying instructions from your DNA for controlling the synthesis of proteins) to locate a mutated gene plus an enzyme, like Cas9, to cut the double-stranded gene helix and create space for functioning genes to be inserted. However, a concern about CRISPR is that the editing could go awry and cause unintended changes in DNA that could trigger health problems. Findings of a study published in the July 2018 edition of the journal Nature Biotechnology found that such inaccuracies, referred to as off-target effects, were substantially higher than originally reported and some were thought to silence genes that should be active and activate genes that should be silent. These off-target effects, such as random insertions, deletions, translocations, or other base-to-base conversions, pose significant challenges for developing policy associated with the technology.

Subsequently however, the paper was retracted, and an error correction was posted on a scientific website. Contrary to their original findings, the authors of the Nature Biotechnology paper restated that the CRISPR-Cas9 gene editing approach, "can precisely edit the genome at the organismal level and may not introduce numerous, unintended, off-target mutations".

Base editing

Notwithstanding, researchers remained concerned about CRISPR’s off target effects and several devised a technique, referred to as base editing, to reduce these. Base editing is described in three research papers published in 2017: one in the November edition of the journal ‘Protein and Cell’, another in the October edition of ‘Science’ the and a third by researchers from the Broad Institute, in the October edition of the journal ‘Nature’. Base editing takes the original CRISPR-Cas9 and fuses it to proteins that can make four precise DNA changes: it can change the letters C-to-T, T-to-C, A-to-G and G-to-A. The technique genetically transforms base pairs at a target position in the genome of living cells with more than 50% efficiency and virtually no detectable off-target effects. Despite its success, there remained other types of point mutations that scientists wanted to target for diseases.

Prime editing

Prime editing is different to previous gene editing systems in that it uses RNA to direct the insertion of new DNA sequences in human cells. According to David Liu, the senior author of the 2019 Nature paper and a world renowned authority on genetics and next-generation therapeutics, “a major aspiration in the molecular life sciences is the ability to precisely make any change to the genome in any location. We think prime editing brings us closer to that goal”. Because prime editing provides a means to be more precise and more efficient in editing human cells in a versatile way, which eliminates many of CRISPR’s unintentional errors, it significantly expands the scope of gene editing for biological and therapeutic research.

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CRISPR-Cas9 genome editing a 2-edged sword

Gene editing positioned to revolutionise medicine

There are around 75,000 different mutations that can cause disease in people and prime editing has the potential to correct up to 89% of known disease-causing genetic variations. According to Liu, "Prime editing is the beginning, rather than the end, of a long-standing aspiration in the molecular life-sciences to be able to make any DNA change in any position of a living cell or organism, including potentially human patients with genetic diseases". Liu’s team at the Broad Institute intends to continue optimizing prime editing. In their October 2019 Nature paper researchers reported that they can precisely correct mutant genes, which cause sickle cell anaemia and Tay Sachs disease.

Sickle cell anaemia and Tay Sachs

Sickle cell anaemia is an inherited form of anaemia. This is when there are not enough healthy red blood cells (haemoglobin) to carry adequate oxygen throughout your body. The condition is the most common inherited blood disorder in the US, affecting 70,000 to 80,000 and further it is estimated each year some 300,000 babies are born with the disorder worldwide. Tay-Sachs disease is a rare and fatal nerve condition often caused by the addition of four extra letters of code. Although anyone can be a carrier of the disease it is much more common among people of Ashkenazi (Eastern European) Jewish descent. In the Ashkenazi Jewish population, the disease incidence is about 1 in every 3,500 new-borns and the carrier frequency is 1 in every 29 individuals.

Some moral and ethical implications of CRISPR

Being able to modify your DNA with CRISPR tools has transformed scientific research and is revolutionising medicine although it will be some time before the technology is regularly used in clinics. In addition to its potential benefits there are significant moral and ethical challenges associated with the technology, especially when it is used for germline engineering, which is the process by which your genome is edited in such a way that the change is heritable. Inappropriate use of germline editing could dent the progress of the CRISPR technology.

The first CRISPR babies

One well publicized inappropriate use of CRISPR is a team in China, led by He Jiankui of the Southern University of Science and Technology in Shenzhen, which in November 2018 “created” the first gene edited twins, known by their pseudonyms Lulu and Nana. He edited the twins’ cells to be immune to HIV infection when they were embryos, therefore ensuring that every cell in their bodies were changed, including their reproductive ones, which means their edited genomes can be passed on to their children and grandchildren, despite the fact that scientists cannot be sure what the long term effects of such lasting modifications might be. The twins are the first CRISPR babies and the first humans to have every cell in their body genetically modified using the technology.

In 2015 Chinese researchers were the first to edit the genes of a human embryo in a laboratory dish. Although the embryos did not go to term, the experiment triggered an international outcry from bioethicists, who argued that CRISPR should not be used to make babies. Notwithstanding, He Jiankui did just this.

He employed CRISPR to alter a gene in IVF embryos to disable the production of an immune cell surface protein, CCR5, which HIV uses to establish an infection before insemination. CCR5 is a well-studied genetic mutation, and there is scientific and medical value in understanding how CRISPR can be used to disable and prevent HIV/AIDS. He believed that the use of CRISPR technology was medically appropriate and expected his experiment, “to produce an IVF baby naturally immunized against AIDS”. But more contentiously, He created twins who could pass the protective mutation to future generations. It is CRISPR’s ability to easily and cheaply edit human embryos, eggs, or sperm in order to create irrevocable changes and the potential for designer babies, which raises concerns.

He defended his work at a Hong Kong genomics conference in late November 2018, but there was immediate and significant international criticism about the scientific and ethical legitimacy of his experiments, which broached China’s guidelines as well as international ethical and regulatory norms. A Chinese government investigation found He to have violated state law in pursuit of “personal fame and fortune”. His endeavours cost him his university position and the leadership of a biotech company he founded, which had successfully raised US$43m start-up capital and was advised by Craig Mello, professor of the University of Massachusetts Medical School and Nobel Laureate for medicine in 2006 for his genetics research.

Opacity and scientific competition

Some scientists are reluctant to be critical of He and suggest his studies, which resulted in the first CRISPR babies, simply signal the “next chapter in the technology’s story”. He Jiankui appears to be an ambitious scientist desperate to become the first to conduct the gene editing experiment on humans, but who made some significant errors of judgement by initiating his study prematurely and by withholding information from regulatory authorities and his university. A generous interpretation might suggest that He was motivated by science and humanity. Through a Beijing-based organization, which helps Chinese people with HIV, he recruited couples for his experiment where only the fathers were living with HIV infections, which they managed by antiviral drugs. Eight couples agreed to participate, although one subsequently withdrew.

Since He’s statement at the Hong Kong conference he has disappeared, but the background to his studies has been well documented. In late 2017, He, who specialized in sequencing DNA, began his efforts to produce human babies from gene edited embryos and before and during his study it is reported that he sought advice from international experts in the field and communicated openly with international colleagues about his plans. Notwithstanding, it is alleged that He faked a blood test for one of the fathers in the study, aware that in China the HIV status of the father would disqualify him from participating in fertility treatments. Also, He failed to appropriately inform the hospital where the twins were edited and implanted of the status of his experiments.

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Will China become a world leader in health life sciences and usurp the US?

Fierce competition among scientists is not uncommon and competition fuels opacity among scientists in their battle to become the first to make a discovery. Indeed, it is not uncommon for scientists to shield their ideas and research. This does not condone He’s actions, but it might help to explain them. Generally speaking, scientific opacity is not created by ambitious scientists alone, but it is partly created by scientific funding bodies and research institutions. Such opacity is a significant obstacle to open collaboration. In addition to wanting to be the first, He’s intentions might also have been an attempt to spare children of parents with HIV/AIDS from inheriting the disease.

CRISPR is not yet safe

Be that as it may, many scientists agree that CRISPR is not yet safe and precise enough to be used in human embryos. In the March 2019 edition of Nature a group of 18 prominent CRISPR scientists and bioethicists from seven countries called for a global moratorium on heritable genome editing until the establishment of an international framework that would compel countries to establish both scientific safety and broad societal agreement before allowing the technology to progress. "We call for a global moratorium on all clinical uses of human germline editing; that is, changing heritable DNA (in sperm, eggs or embryos) to make genetically modified children" , the scientists wrote.

Opposition to germline editing is mixed

However, opposition to germline editing is mixed. In February 2017 the US National Academies of Sciences, Engineering, and Medicine (NASEM) published a report, which did not call for an international ban of germline editing, but instead suggested that it "might be permitted" if strict criteria were met. In July 2018, the UK’s Nuffield Council of Bioethics published a report on heritable genome editing and suggested that under certain circumstances it could be morally permissible, even in cases of human enhancement.

Given that CRISPR is cheap, easy-to-use and already an effective tool in thousands of laboratories throughout the world, it seems reasonable to assume that standards and laws are unlikely to prevent a determined scientist and desperate patients from using the technology prematurely. Indeed, science and medicine have a history of researchers attracting public criticism for undertaking experiments prematurely only to have those experiments become common medical practices: in-vitro fertilization (IVF) is one such example. Although IVF has a chequered history today it accounts for millions of births worldwide and 1% to 3% of all births every year in the US and Europe.

Germline engineering and somatic genetic modification

Here we describe the difference between germline and somatic adjustments. The former uses CRISPR to modify DNA in such a way that the change is heritable. The latter uses CRISPR to modify the DNA of people with incurable diseases in a way that such modifications are limited to the people treated and not passed on to future generations. Broadly speaking, your body has two kinds of cells: somatic and germ cells. The vast majority are somatic. These cells make up your body and are responsible for forming all your familiar structures: such as your skin, blood, muscles and organs etc. Your somatic cells die when you die so there is no chance of them creating a new organism. However, germ cells are different. Early in your development your germ cells are sequestered: they divide more slowly and under restricted circumstances. Germ cells cannot become a physical feature such as an ear or a finger, but they do make the only bits of you, which can form a new person: your eggs and your sperm. Every cell in your body holds your DNA in an unbroken lineage stretching back millions of years and thousands of generations, but only the germline has a chance to go forward. Human germline modification means deliberately changing the genes passed on to children and future generations and thereby creating genetically modified people. Somatic genetic modification is different. It adds, cuts, or changes the genes in some of your cells, typically to alleviate a medical condition. The use of human genome editing to make edits in somatic cells for purposes of treating genetically inherited diseases is already in clinical studies. If perfected, somatic gene editing (gene therapy) holds promise for helping people who are sick, affecting only an individual consenting patient. With the exception of He’s studies, human clinical studies with CRISPR have been limited to somatic cells. In effect, this renders CRISPR no more consequential than any other experimental drug or treatment. Any CRISPR-made somatic cell changes are a genetic dead-end and are not heritable. However, germline cells have the possibility of immortality, with the potential to affect thousands of people over the course of several generations. Tampering with germline cells is therefore a much more serious proposition.

Clinical studies of gene therapies

Gene therapy is primarily available in a research setting. The US Food and Drug Administration (FDA) has approved only a limited number of gene therapy products for sale in the US.According to the US National Institutes of Health, which serves as a clearinghouse for biomedical research worldwide, there are over 800 clinical studies currently underway to test gene therapy as a treatment for genetic conditions. The list includes a relatively small number of CRISPR studies as a treatment for cancers of the lung, bladder, cervix and prostate, the majority of which are in China where doctors appear to be leading the race to treat cancer by editing genes. For the past two decades China has been investing heavily in biomedicine. It is one way that China is able to compete with the West and demonstrate its technological prowess in the 21st century. Also, it is important for China to keep its vast population healthy in the 21st century. Given the somewhat ambiguous state of CRISPR technology it seems reasonable to assume that the first therapeutic applications of CRISPR will be in diseases where cells can be taken out of your body, edited, checked to ensure they are safe and then reintroduced. This suggests blood disorders such as sickle cell or thalassemia.

Takeaways

Bioethicist Henry T (Hank) Greely, professor at Stanford University, California, US, compares CRISPR to the Model T Ford, which was not the first automobile, but because of its simplicity of production, dependability and affordability it transformed society. CRISPR is not the first gene editing technology, but it is cheap and easy to use and is on the cusp of transforming biomedicine. A significant challenge is getting CRISPR tools, which are capable of performing gene edits, into the right place and to ensure they are safe. Prime editing is a smart, innovative and a substantial step forward in achieving this. Indeed, David Liu and his colleagues from the Broad Institute have expanded the gene editing toolbox to facilitate ever-more precise editing ability and efficiency. Significantly, the overwhelming majority of human genetic disorders are due to the types of mutation that prime editing is able to correct, which stands the technique in good stead to be useful in therapies for intractable diseases. Notwithstanding, it is one thing to cut out sequences of DNA that cause genetic diseases and another to make genetic changes that are passed down to all later generations. Because CRISPR is cheap, easy-to-use, in the hands of scientists throughout the world, and already has been used to create babies with heritable traits, the technology provokes deep ethical and societal debate about what is, and what is not acceptable in efforts to prevent disease. Given that CRISPR has the potential to change the nature of humanity, it is incumbent on all citizens, not just scientists, bioethicists and regulators, to call for open and inclusive processes associated with all aspects of CRISPR.

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Will China become a world leader in health life sciences and usurp the US?

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Will China become a world leader in health life sciences and usurp the US?

After World War II, the US captured the global lead from Europe in life sciences thanks to the large American domestic market, its strong network of university research laboratories, competent regulation, effective pricing regimens and generous federal R&D funding.

America’s leadership in life sciences is slipping

Over the past two decades, as China has systematically upgraded its economy from low-grade to high-grade production, it has come to realize the significance of the health life sciences and Beijing has become determined to win a larger share of the industry’s activity. During this time America’s leadership position in the life sciences industry has slipped.

Will China usurp the US and become a world leader in health life sciences?
What could the erosion of the life sciences industry mean for the US economy?
What can American life sciences corporations do to reduce or slow their market slippage?

Health life sciences

Health life sciences refers to the application of biology and technology to improve healthcare. It includes biopharmaceuticals, medical technology, genomics, diagnostics and digital health and is one of the future growth industries positioned to radically change the delivery of healthcare, substantially reduce the morbidity and mortality of a range of chronic and incurable diseases and save healthcare systems billions. The life sciences industry plays a key role in supporting the economies of the US and China as well as other nations and helps them to compete internationally. The sector requires a complex ecosystem, which integrates high-tech research, large, long-term investments of capital in the face of significant technological, market and regulatory risks, skilled labour, specific manufacturing skills, intellectual property (IP) protection and policy support. According to a 2019 Deloitte’s report on health life sciences the global market size of the industry is projected to grow from US$7.7trn in 2017 to US$10trn by 2022.

Reason’s for America’s slippage

America’s slippage in its life sciences industry is due to:

Increased fair competition from a number of nations, including the UK, and increased unfair competition from China who aggressively steals US IP to piggyback on American life-sciences innovations in order to benefit from enhanced therapies without having to pay their fair share for the costly R&D. China then uses its government’s monopsony power as a purchaser of life sciences offerings to limit the prices of US and other international firms
Recent US Administrations’ lukewarm support for the industry. Federal biomedical research funding has been cut in real terms. Reimbursement policies are changing to a value-based approach and pricing policies have tightened. Such policies create uncertainty regarding the government’s willingness to pay for future treatments and the research necessary to discover and bring them to market. The US is also falling behind in providing innovative tax incentives for the industry
American life sciences corporations’ reluctance and inability to adapt their strategies and business models to changing international markets.

Permanent economic damage

The Chinese competitive threat is real and significant. It is important for the US to maintain a competitive life-sciences sector since it generates high-skilled, high-paying jobs and its product offerings are sold throughout the world and the industry is a key component of the US traded economy. A weaker American competitive position in the life sciences could mean a lower value for the dollar, a larger trade deficit, plant closures and job losses. China and other nations, which are gaining global market share at the expense of the US, could cause significant damage to the American life-sciences industry.

Creating a health life sciences industry is challenging enough, recreating one after it has lost significant market share is even more challenging, if not impossible. We suggest that to reduce to possibility of this happening US life sciences corporations might consider changing the mindsets of their leaders and demonstrate a greater willingness to learn from and engage with Chinese start-ups, especially those in adjacent industries with AI and machine learning capabilities and experience. The cost of doing this will be to give up some IP, which might be worth doing given the potential financial benefits from such a strategy.

A “bullish” American perspective

The generally accepted Western perspective is that the US excels at visionary research and moon-shot projects and will always be the incubator for big ideas. The reasons for this include: (i) American education is open, encourages individuality and rewards curiosity and its universities have consistently produced vast numbers of innovative discoveries in the life sciences, (ii) American scientists have been awarded the majority of Nobel prizes in physiology/medicine, physics and chemistry, and (iii) America is the richest nation in the world. This suggests that there are no apparent reasons why the US should not continue as a world leader in health life sciences.

By contrast, China has stolen and copied America’s intellectual property (IP) for years and is a smaller economy fraught with politico-economic challenges. Although China’s economic growth has lifted hundreds of millions of people out of poverty, China remains a developing country with significant numbers of people still living below the nation’s official poverty level. Beijing has challenges balancing population growth with the country’s natural resources, growing income inequality and a substantial rise in pollution throughout the country. Further, China’s educational system is conformists and not geared to producing scientists known for making breakthrough discoveries. This is borne-out by the fact that China only has been awarded two Nobel prizes for the sciences: one for physiology and medicine in 2015 and another for physics in 2009.

Copiers rather than inventors

Over the past four decades Chinese scientists, with the tacit support of Beijing, have aggressively and unethically stolen Western technologies and scientific knowhow. According to findings of a 2017 research report from the US Intellectual Property (IP) Commission entitled The Theft of American Intellectual Property, the magnitude of "Chinese theft of American IP currently costs between US$225bn and US$600bn annually."

America’s response to China’s IP theft has been to adopt the moral high-ground, dismiss China as an unscrupulous nation not worthy of investment and focus on commercialising its discoveries with “single bullet” product offerings and marketing them in wealthy regions of the world, predominantly North America, Europe and Japan. Over the past decade, this strategy has been supported by a US Bull market in equities, which started in 2009, outpaced economic growth in most developed nations and led to a significant degree of satisfaction among C-suites and boards of directors of US life sciences corporations, which did not perceive any need to adjust their strategies and business models despite some market slippage and changing market conditions.

Confucian values support conformism rather than discovery

Although China has benefitted economically from the theft of American IP, the American view tends to be that China is unlikely to become a world leader in the life sciences because the nation has not produced a cadre of innovative scientists and its education system is unlikely to do so in the near to medium term. Chinese education encourages students to follow rather than to question. Indeed, Confucian values remain a significant influence on Chinese education and play an important role in forming the Chinese character, behaviour and way of living. Confucianism aims to create harmony through adherence to three core values: (i) filial piety and respect for your parents and elders, (ii) humaneness, the care and concern for other human beings, and (iii) respect for ritual. According to Confucian principles, “a good scholar will make an official”. Thus, some of China’s best scientists leave their laboratories for administrative positions.

Further, Chinese universities tend to bind students to their professors who expect unquestioning loyalty. Scepticism towards generally accepted scientific theories is discouraged, especially when they are held by senior academics. Also, China unlike the US, does not tolerate “failure”, and this incentivises Chinese scientists to conduct “safe” research that yields quick and “achievable” outcomes. All these factors conspire to discourage high risk creative scientific activity and encourages safer, “copycat” research endeavours.

The strength of the US$ and the US economy

America’s global leadership in the life sciences is supported by the fact that the US is the world’s richest and most powerful nation. In nominal terms (i.e., without adjustment for local purchasing power) the US and China have GDPs of US$19trn and US$12trn respectively and populations of 326m and 1.4bn. Further, the US has an “unrivalled” global trading position: the US dollar is the strongest currency in the world and dominates the overwhelming percentage of all international trade settlements: 70% of all world trade transactions are in US$, 20% in €’s and the rest in Asian currencies, particularly the Japanese ¥ and increasingly the Chinese ¥. Also, US dollar holdings make up the largest share of foreign exchange reserves and the effect of this is to maintain the high value of the US$ compared with other currencies and provide US corporations with significant profits, US citizens with cheap imports and the US government with the ability to refinance its debts at low interest rates.

An Asian context

We suggest that it is increasingly important for American health life science professionals to get a better understanding of China and Asia. The Asian perspective described here is drawn from three recent books: The New Silk Roads: The Present and Future of the World by Peter Frankopan, The Future is Asian by Parag Khanna and AI Super-Powers: China, Silicon Valley and the New World Order published in late 2018 by Kai-Fu Lee.

Crudely put: the 19^th century was British, the 20^th century American and the 21^st century is expected to be Asian. The era of breakthrough scientific discoveries and stealing American IP is over, and we have entered an “age of implementation”, which favours tenacious market driven Chinese firms. “Asians will determine their own future; and as they collectively assert their interests around the world, they will determine ours as well”, says Khanna. This is starkly different to American prognosticators who assume that the world will be made in the American image, sharing American values and economics.

Asian view of the US$

Some observers suggest that there are chips appearing in the giant US edifice of international trade described above. The current US Administration’s policies have triggered and intensified discussions in Europe and Asia about America’s dominant global economic position and suggest that the US$ might be starting to weaken against a basket of currencies as China, Russia, Iran, Turkey and other nations, choose to use local currencies for some international trade transactions, which they then convert into gold. Further, central banks are tightening their monetary policies and adjusting their bond purchasing strategies. A common US view is that such trading activities are so small relative to global US$ transactions they will neither weaken the US$ nor dent America’s pre-eminent global trading position.

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Notwithstanding, replacing the US$ with the Chinese ¥ seems to be part of Beijing’s long-term strategy, as Beijing encourages its trading partners to accept the ¥ as payment for Chinese exports. China’s recent trading agreements with Canada and Qatar for instance have been based upon local currencies rather than the US$. China, which is the biggest importer of oil, is preparing to launch a crude oil futures contract denominated in Chinese ¥ and convertible into gold. European, Asian and Middle Eastern countries have embarked on domestic programs to exclude the US$ from international trade transactions. Also, oil exporting countries are increasingly able to choose which currencies they wish to trade in. At the same time, oil-producing countries no longer seem so interested in turning their revenues into “petrodollars. For the past decade, President Putin of Russia has been calling for the international community to re-evaluate the US$ as the international reserve currency. All this and more suggests that increasingly, emerging economies may transition from their undivided dependence on the US$ for international trade settlement to a multipolar monetary arrangement. Whilst small relative to the full extent of global trade, it is instructive to view these changes within a broader Asian context.

The US has had little exposure to China and Asia

One outcome of America’s pre-eminent global economic position and the financial success of American life sciences companies is that corporate leaders and health professionals tend to have little or no in-depth exposure to Chinese and Asian culture and markets. For example, few Fortune 500 senior executives have worked in China; few American life sciences corporations have sought in-depth briefings of Asian markets and few US students and scientists have studied or carried out research in China. Instead, American life science corporate leaders tend to be US-centric; they condemn China for its IP theft and recommend not to invest in China because a condition of doing so is that you are obliged to part with some of your IP.

Asia a potential economic powerhouse

This distancing has resulted in life science professionals “misdiagnosing” China in a number of ways, which we will discuss. One misdiagnosis is to conflate China with Asia. Asia is comprised of 48 countries. East Asia includes China, Japan and North and South Korea. South Asia includes India, Pakistan and Bangladesh. South East Asia includes Indonesia, Malaysia, Philippines, Singapore and Thailand. These three sub-regions link 5bn people through trade, finance, infrastructure and diplomatic networks, which together represent 40% of the world’s GDP. China has taken a lead in building new infrastructure across Asia - the new Silk Roads - but will not necessarily lead this vast region alone. Rather, as Khanna reminds us, “Asia is rapidly returning to the centuries-old patterns of commercial and cultural exchanges, which thrived long before European colonialism and American dominance”.

The difference between IP theft and imitating ‘what works’

Market driven Chinese start-ups, supported by the government, are expected to transform China into a world leader in health life sciences by 2030. The thing to understand about China is that it is not just a few start-ups that steal and copy American IP but thousands, which then aggressively compete. This entails cutting prices, improving and adapting their product offerings, developing leaner operations and aligning their strategies and business models to the demands of different markets. The vast scale of this activity has led to a unique cadre of über agile Chinese entrepreneurs, who imitate successful business models and then engage in value added culture-specific product development processes. This has led to Chinese companies becoming exemplary “market driven” implementors. By contrast American companies tend to be “mission driven” and operate a “single bullet” business model and are either slow or reluctant to adapt to the demands of different markets. This results in US discoveries being exploited in Asia by Chinese rather than American companies. We suggest that there are significant benefits to be derived from American life sciences companies developing joint ventures with market driven Chinese start-ups even if it means surrendering some IP.

As a postscript, it is worth pointing out that the first Chinese patent was only granted in 1985 and recently, after decades of widespread theft, IP protection in China has improved at lightning speed. As Chinese companies issue more patents, the keener they are to protect them. According to the World Intellectual Property Organization in 2017 China accounted for 44% of the world’s patent filings, twice as many as America.

US inventions exploited in Asia by Chinese start-ups

An illustration of a disruptive life science technology invented in the US but exploited faster and more extensively in China is CRISPR-Cas9 (an acronym for Clustered Regularly Interspaced Short Palindromic Repeats), which is generally considered to be the most important invention in the history of biology. The initial discovery was made in 2012 by a collaboration between Jennifer Doudna, at the University of California, Berkeley, USA and French scientist Emmanuelle Charpentier. Applications of CRISPR technology are essentially as infinite as the forms of life itself. Since its discovery, modified versions of the technology by Chinese scientists have found a widespread use to engineer genomes and to activate or to repress the expression of genes and launch numerous clinical studies to test CRISPR-Cas9 in humans.

Virtuous circle

Notwithstanding, transforming CRISPR genomic editing technologies into medical therapies requires mountains of data and advanced AI capabilities. China has both. The more genomic data you have the more efficacious clinical outcomes are likely to be. The better your clinical outcomes the more data you can collect. The more data you collect the more talent you attract. The more talent you attract the better the clinical outcomes. China is better positioned than America to benefit from this virtuous circle. China’s less than stringent regulation with regards to privacy and storing personal data gives it a distinct competitive advantage over American and Western life sciences companies. China also has more efficient means than any Western nation for collecting and processing vast amounts of personal data.

Collecting personal data

Any casual visitor to China will tell you that one of the striking differences with Western nations is that the Chinese economy is cashless and card-less. Citizens pay for everything and indeed organise their entire lives with a mobile app called WeChat, a multi-purpose messaging, social media and mobile payment app developed by Tencent. WeChat was first released in 2011 and by 2018 it was one of the world's largest standalone mobile apps, with nearly 1bn daily users who every day send about 38bn messages. Not only is WeChat China's biggest social network it is also where people turn to book a taxi, hotel or a flight, order food, make a doctor’s appointment, file police reports, do their banking or find a date and has become an integral part of the daily life of every Chinese citizen. State-run media and government agencies also have official WeChat accounts, where they can directly communicate with users. Further, an initiative is underway to integrate WeChat with China’s electronic ID system. It may be hard for people outside of China to grasp just how influential WeChat has become. There is nothing in any other country that is comparable to WeChat, which captures an unprecedented amount of data on citizens that no other company elsewhere in the world can match. This represents a significant competitive advantage. Applying AI and machine learning technologies to such vast data sets provide better and deeper insights and patterns. These vast and escalating data sets, and advanced AI capabilities for manipulating them, give China a significant competitive advantage in the high growth life sciences industry, which increasingly has become digital.

Processing personal data

AI is another example of a technology invented in the West and implemented much faster in China. The “watershed” moment for China was in 2017, when AlphaGo became the first computer program to defeat a world champion at the ancient Chinese game of Go. Since then, China has been gripped by “AI fever”.

Until recently AI machines were not much better than trained professionals at spotting anomalies and mutations in assays and data. This changed in early-2,000 with the ubiquitous spread of mobile telephony and the confluence of vast data sets and the development of neural networks, which made the onerous task of “teaching” a computer rules redundant. Neural networks allow computers to approximate the activities of the human brain. So, instead of teaching a computer rules, you simply feed it with vast amounts of data and neural networking and deep learning technologies identify anomalies and mutations in seconds with exquisite accuracy.

The Beijing Genetics Institute

An illustration of the scale and seriousness of China’s intent to become a world-leader in life sciences and to eclipse similar initiatives by the US is the 2016 launch of a US$9bn-15-year national initiative to develop technologies for interpreting genomic and healthcare data. This national endeavour followed the launch in 1999 of the Beijing Genomics Institute (BGI), which today is a recognised global leader in next generation genetic sequencing. In 2010, BGI received US$1.5bn from the China Development Bank, recruited 4,000 scientists and established branches in the US and Europe. In 2016 BGI created the China National GeneBank (CNGB) on a 47,500sq.m site in Shenzhen, which benefits from BGI’s high-throughput sequencing and bio-informatics capacities. CNGB officially opened in July 2018 and is the largest gene bank of its kind in the world. Dozens of refrigerators can store samples at temperatures as low as minus 200 degrees Celsius, while researchers have access to 150 domestically developed desktop gene sequencing machines and a US$20m Revolocity machine, known as a “supersequencer”. The Gene Bank enables the development of novel healthcare therapies that address large, fast growing and underserved global markets and to further our understanding of genomic mechanisms of life. Not only has CNGB amassed millions of bio-samples it has storage capacity for 20 petabytes (20m gigabytes) of data, which are expected to increase to 500 petabytes in the near future. The CNGB represents the new generation of a genetic resource repository, bioinformatics database, knowledge database and a tool library, “to systematically store, read, understand, write, and apply genetic data,” says Mei Yonghong, its Director.

US life sciences benefit by engaging with Chinese companies

Lee, in his book about AI, suggests that it is not so much Beijing’s policies that keep American firms out of the Chinese markets, but American corporate mindsets, which misdiagnose Chinese markets, do not adapt to local conditions and fail to understand the commercial potential of Chinese start-ups and consequently get squeezed out of the Chinese market.

This is what happened as Google failed to Baidu, Uber failed to DiDi, Twitter failed to Weibo, eBay failed to TaoBao, and Groupon failed to Meituan-Dianping. We briefly describe the demise of Groupon and point to lessons, which can be learned from it.

Lessons from Groupon’s failure in China

Groupon failed to adapt its core offering when group discounts in China faded in popularity and as a consequence it rapidly lost market share. Meituan, founded in 2010 as a Chinese copy of Groupon, quickly adapted to changing market conditions by extending its offerings to include cinema tickets, domestic tourism and more importantly, “online-to-offline” (O2O) services such as food and grocery delivery, which were growing rapidly.

In October 2015, Meituan merged with Dianping, another Chinese copy of Groupon, to become Meituan-Dianping the world's largest online and on-demand booking and delivery platform. The company has become what is known as a transactional super app, which amalgamates lifestyle services that connect hundreds of millions of customers to local businesses. It has over 180m monthly active users and 600m registered users and services up to 10m daily orders and deliveries. In the first half of 2018 Meituan-Dianping facilitated 27.7bn transactions (worth US$33.8bn) for more than 350m people in 2,800 cities. That is 1,783 enabled services every second of every day, with each customer using the company’s services an average of three times a week. Meituan-Dianping IPO’d in 2018 on the Hong Kong stock exchange and raised US$4.2bn with a market cap of US$43bn.

Efficiency also drives innovation. Meituan-Dianping’s Smart Dispatch System, introduced in 2015, schedules which of its 600,000 motorbike riders will deliver the millions of food orders it fulfils daily. It now calculates 2.9bn route plans every hour to optimize a rider’s ability to pick up and drop off up to 10 orders at once in the shortest time and distance. Since Smart Dispatch launched, it has reduced average delivery time by more than 30% and riders complete 30 orders a day, up from 20, increasing their income. In 2019, the American business magazine Fast Company ranked Meituan-Dianping as the most innovative company in the world.

Takeaways

Although Meituan-Dianping and other companies we mention may not be well known in the West and are not in the health life sciences industry, they are engaged in highly complex digital operations disguised as simple transactions, which enhance the real-world experiences of hundreds of millions of consumers and millions of merchants. To achieve this the companies have amassed vast amounts of data and have perfected AI and machine learning technologies, which make millions of exquisitely accurate decisions every hour, 24-7, 365 days a year. Such AI competences are central to the advancement of health life sciences. American life science professionals might muse on the adage: “make your greatest enemy your best friend” and consider trading some of their IP to joint venture with fast growing agile Chinese data companies in a strategy to restore and enhance their market positions.

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CRISPR-Cas9 genome editing a 2-edged sword

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CRISPR-Cas9 genome editing technology discovered in 2012 has revolutionized biological science and brought hope to millions of people born with incurable inherited killer diseases
In July 2018 the UK’s Nuffield Council on Bioethics endorsed the technology to make changes at the cell level in the human body that are heritable
This alarms bioethicists because there is no universally agreed regulation for CRISPR and the technology is cheap, easy-to-use and accessible and the line between “therapy” and “enhancement” is blurred
CRISPR was invented in the West but is rapidly being transformed into therapies in China where regulation is less than stringent
Will genome editing be used to enhance off-springs that satisfy parents’ preferences for children with specific characteristics?

CRISPR-Cas9 genome editing a 2-edged sword

The genie is out of the bottle!

On the 17^th July 2018 the UK’s Nuffield Council on Bioethics published a report entitled, Genome Editing and Human Reproduction: Social and Ethical Issues, which concluded that germline editing, a process by which every cell in the human body could be altered in such a way that the change is heritable, is “morally permissibly” under certain circumstances. The Council was referring to developments of an invention made in 2012 by scientists Jennifer Doudna, and Emmanuelle Charpentier. They discovered how to exploit an oddity in the immune system of bacteria to edit genes, which resulted in CRISPR-Cas9, (an acronym for Clustered Regularly Interspaced Short Palindromic Repeats), which is generally considered the most important invention in the history of biology. Since its discovery, modified versions of the technology have found a widespread use to engineer genomes and to activate or to repress the expression of genes. Clinical studies testing CRISPR-Cas9 in humans are underway.

In this Commentary

In this Commentary we: (i) describe CRISPR-Cas9 and indicate how it has impacted medicine, biotechnology and agriculture, but suggest that it is most famous for its potential to modify human embryos to provide therapies for inherited killer diseases for which there are no known cures, (ii) suggest that although the technology is gaining regulatory support for its use in humans, there is no universal regulatory agreement. Some countries remain opposed to using CRISPR to edit human embryos while in China regulations is less than stringent. This patchy and loose state of affairs raise concerns among bioethicists, (iii) describe a non-profit agency that has significantly increased the accessibility of the technology, which has helped to democratise CRISPR, but also makes it easier for less stringently controlled laboratories to acquire it, (iv) briefly describe the Chinese scientists first use of the technology in humans and some of the unintended consequences which resulted. We provide examples of research that followed and briefly describe the US-China race to transform CRISPR into viable therapies, and suggest that China, helped by laxed regulation, is winning the race, (v) suggest that these factors, plus the fact CRISPR blurs the distinction between ‘therapy’ and ‘enhancement’, seems to convince bioethicists that the technology at some point in the future will be used to create ‘designer babies’, (vi) conclude by noting that for millennia people have been using radical and painful methods to modify their own and their children’s bodies and this seems to suggest that in time, germline editing will be perceived as a logical extension of these customs and practices, the genie is out the bottle and customize children are likely to become the norm.

CRISPR-Cas9

CRISPR is a mechanism deployed by bacteria to identify the DNA of invading viruses and is used by scientists to target a specific gene. Cas-9 is an enzyme, which acts like a pair of molecular scissors to cut out a piece of DNA and, if need be, replace it with a new gene. The process is faster, cheaper and easier to use than traditional genetic modification and has been likened to editing a Word document on a computer. Thus, gene editing has been taken away from highly skilled and tightly regulated molecular biologists and made more widely available. This not only democratizes science but also heightens ethical concerns.

CRISPR technologies impact medicine biotechnology and agriculture

Since the breakthrough was made in 2012, CRISPR-Cas9 has quickly development into a powerful, cheap and accessible tool in genetics. The technology is programmable, efficient, precise and scalable and has driven significant advances across medicine, biotechnology and agriculture throughout the world. As the world’s population and average temperatures increase, the demand for larger, more nutritious harvests and climate-adaptable crops will grow. The application of CRISPR technology to agriculture allows for an efficient and accurate mode of genetic manipulation to meet these increasing needs. The technology also has been used in the fight against malaria. According to a 2018 World Health Organization report, in 2016 there were 216m cases of malaria worldwide and 445,000 deaths from the disease. Malaria is spread by the female Anopheles-gambiae mosquito, which is one of 3,500 species of mosquitoes. Scientists have used CRISPR technology to edit the genes of this specific type of mosquito to avoid the malaria causing parasite. In a study carried out at Imperial College London and published in the September 2018 edition of Nature Biotechnology researchers succeeded in destroying a population of trapped Anopheles mosquitoes by using CRISPR technology to genetically alter cells to spread a genetic modification that blocks female reproduction so, over time, the malaria spreading Anopheles mosquitoes die out. The research demonstrates how a specific CRISPR application can propagate a particular suite of genes throughout an entire population or species and empower scientists in the war against diseases. “It provides hope in the fight against a disease that has plagued mankind for centuries,” says Andrea Crisanti, lead author of the Imperial study.

But the one application, which has made CRISPR famous is the modification of the human genome, which promises to cure some of the world’s deadliest diseases for which there are no known therapies. There are some 10,000 genetic diseases of which less than 6% have approved treatments.

Regulatory support

CRISPR genome editing technologies have been gaining regulatory acceptance for their use in humans and an increasing number of scientists in the US, UK and China have reached conclusions similar to those of the Nuffield Council, and suggest that if germline editing is shown to be safe and there are no medical alternatives, it should be permitted to prevent children being born with fatal diseases. In 2017, the UK’s Human Fertilization and Embryology Authority approved an application to use genome editing, which allows scientists to change an organism’s DNA in research on human embryos. Also, in 2017 a report from the US National Academy of Sciences (NAS) stated that clinical trials for editing-out heritable diseases could be permitted in the future for serious conditions under stringent oversight. At the same time as the Nuffield Council published its findings, - July 2018 - the US Food and Drug Administration (FDA) Commissioner Scott Gottlieb announced a new regulatory framework for genome editing for rare diseases. The following month, - August 2018 - the FDA along with the US National Institutes of Health (NIH) issued joint guidelines for a new streamlined process for assessing the safety of gene-therapy human clinical studies. And in an August 2018 New England Journal of Medicine editorial Gottlieb and NIH Director Francis Collins argue that, “there is no longer sufficient evidence to claim that the risks of gene therapy are entirely unique and unpredictable - or that the field still requires special oversight that falls outside our existing framework for ensuring safety.”

No international regulatory framework for CRISPR triggers concerns

Despite increasing support for genome editing, to-date no internationally agreed regulatory framework exists that addresses the ensuing scientific, socio-ethical and legal challenges CRISPR technologies pose for regenerative and personalised medicine. Regulation is on a country-by-country basis and most nations struggle to assess whether gene editing may or may not be different from classical genetic engineering. Several nations remain opposed to the use of the technology in humans. The most contentious issue is human germline editing.

In Canada human germline editing is a criminal offence and sanctions range from fines of US$400,000 and up to ten years imprisonment. However, there is mounting pressure from Canadian scientists to change the law. France restricts genome editing research and supports the Oviedo Convention, which is the first multilateral binding instrument entirely devoted to bio-law. It came into force in 1999, backed by the Council for Europe and aims to prohibit the misuse of innovations in biomedicine. The treaty states that, “An intervention seeking to modify the human genome may only be undertaken for preventive, diagnostic, or therapeutic purposes and only if its aim is not to introduce any modification in the genome of any descendants”. In Germany germline editing is constrained by its 1990 Embryo Protection Act, which prohibits the generation and use of embryos for basic research, and also prohibits the harvesting of embryonic cells. South Korea’s Bioethics and Biosafety Act prohibits genetic experimentation, which modifies human embryos. Western observers suggest that regulation in China is “thin” and tends to be at the provincial and hospital levels. It has been reported that Chinese hospital review boards have approved clinical studies involving gene-editing and cancer patients without fully understanding the nature and power of the technology.

The “dark-side” of CRISPR technology

Weak regulation raises concerns about the level of ethical conduct in clinical studies and the potential dangers this holds for future therapies. Cognisant of CRISPR’s powerful capabilities, its relative cheapness and accessibility, (see below) James Clapper, the former US Director of National Intelligence describes CRISPR-Cas9 gene editing in the 2016 and 2017 Agency’s Worldwide Threat Assessment reports submitted to the US Congress as, “a potential weapon for mass destruction”. Jennifer Doudna, one of the inventors of CRISPR-Cas9 says that there are things which you would not want the technology used for and, “most of the public does not appreciate what is coming”. These sentiments resonate with bioethicists concerned about the absence of stringent universal regulation and the technology getting into the “wrong hands” and resulting in “designer babies”, an escalation of societal inequalities and increased safety and biosecurity issues.

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The global competition to translate genomic data into personal medical therapies

PART 1

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PART 2

Democratizing the CRISPR technology

Notwithstanding, many scientists view the ease of access to CRISPR technologies as a significant driver of cutting-edge research and the speed at which therapies for life-threatening diseases will enter clinics. The organization most responsible for CRISPR’s widespread accessibility is Addgene, a self-sustaining, non-profit plasmid repository, which facilitates the exchange of genetic material between laboratories throughout the world. (A plasmid is a small DNA molecule within a cell that is physically separated from a chromosomal DNA. It can replicate independently and is used in the laboratory manipulation of genes). It is free for scientists to deposit plasmids in Addgene and a nominal fee is charged for requests. This allows for maintenance and growth of the repository without reliance on grants or external funding. Founded in 2004, Addgene has significantly reduced the frustration scientists experience sharing plasmids with one another. The organization has developed into an important one-stop-shop for depositing, storing, and distributing plasmids globally and this has significantly enabled the democratization of CRISPR technologies. More than 6,300 CRISPR-related plasmids have been developed by over 330 academic laboratories throughout the world and deposited with Addgene. Since 2013, the organization has distributed over 100,000 CRISPR plasmids to some 3,400 laboratories in more than 75 countries.

Mixed results when CRISPR was first used in humans

CRISPR technology was first used in humans in China, when a group of scientists led by Junjiu Huang from Sun Yat-sen University in Guangzhou, attempted to modify the gene responsible for β-thalassemia, a potentially fatal blood disorder. Although the genomes of human embryos edited by the scientists could not be developed into a foetus, the researchers had difficulties publishing their findings because of ethical concerns. After being rejected by the journals Science and Nature their paper was published in 2015 in the journal Protein & Cell. The work triggered an international debate, but the research had a low success rate: only 4 of the 54 embryos that survived the technique carried the repaired genes. Huang and his colleagues identified two challenges. One was unintended genetic modifications - off target effects - when CRISPR either changes a gene scientist did not want changed or it fails to change a gene that they did. The second was that embryos, which did not get edited correctly mixed with those that did and became what is referred to as a “mosaic”.

New study discovers the deletion of thousands of DNA bases

Initially, these anomalies were thought to be minimal and improvements to the technique were thought to be able to reduce them so that they were virtually undetectable. Indeed, since 2015 the science of human genome editing has advanced significantly and there has been an explosion of research. In 2017 alone, there were some 3,500 research papers published on CRISPR technologies but concerns about CRISPR’s accuracy remain. During the past three years of intense research CRISPR-Cas9 became popularly perceived as a technique that can edit genetic code to correct defects inside individual cells and prevent and heal many intractable illnesses. Notwithstanding, also there has been a growing concern among scientists that because Cas9 enzymes reprogram the DNA of a cell, which is the fundamental building block for the development of an organism, the technique, if inaccurate, may cause more harm than good. Recent research supports this view. A study published in the July 2018 edition of the journal Nature Biotechnology discovered deletions of thousands of DNA bases, including at spots far from the edit. Some of the deletions can silence genes that should be active and activate genes that should be silent, including cancer-causing genes. This suggests that previous methods for detecting off-target mutations may have underestimated their true scale and therefore the potential for unintended consequences when using CRISPR technologies might be higher than originally thought. This finding poses a significant challenge for developing policy associated with CRISPR because you do not know what off-target effects will occur in humans until you use the technology.

Who is developing CRISPR-Cas9 therapies?

Notwithstanding, CRISPR–Cas9 is fast entering mainstream R&D and is perceived as a principal technology for treating diseases with a genetic basis and is increasingly playing a significant role in drug discovery. Scientists use the technology to either activate or inhibit genes and can determine the genes and proteins that cause or prevent specific diseases and thereby identify targets for potential therapies. Notwithstanding, drug development is a long and expensive process: it can take more than a decade and cost some US$2bn for researchers to move from the discovery of a target molecule to the production of a clinically approved therapy. So, it could be some time before the first drugs using CRISPR–Cas9 gene editing make it to the clinics. Notwithstanding, a lot has been achieved in a relatively short time.

Research examples

UK examples of research using CRISPR technology include scientists from the Huntington’s Disease Centre at University College London’s Institute of Neurology, who in 2017 completed the first human genetic engineering study, which targeted the cause of Huntington’s disease and successfully lowered the level of the harmful huntingtin protein that irreversibly damages the brains of patients suffering from this incurable degenerative condition. In another study using CRISPR technology and published in a 2017 edition of the New England Journal of Medicine, researchers from Barts Health NHS Trust and Queen Mary University London made a significant step towards finding a cure for haemophilia A, a rare incurable life threatening-blood disorder, which is caused by the failure to produce certain proteins required for blood clotting.

Human clinical studies

Although CRISPR has proved its worth as a research tool, its use as a therapeutic is still uncertain. This is partly because the technology is so new there is a dearth of data upon which to base clinical evaluations. Notwithstanding, since Chinese scientists first used CRISPR to edit a human embryo's genome, new and more accurate variants of CRISPR have been developed. At about the same time - 2015 - that Huang published his findings using CRISPR for the first time in humans, two children with Acute Lymphoblastic Leukaemia, an incurable cancer, were treated at Great Ormond Street Hospital (GOSH) in London with a version of CRISPR called CAR-T cell therapy. This entails extracting blood cells from patients, then using CRISPR technologies to edit the T cells outside the body - ex vivo gene therapy - in order to transform the cells into enhanced cancer fighters before reintroducing them back into the patient’s blood stream. The treatment proved to be such a success that in 2018 CAR-T cell therapy was made available on the NHS. A US clinical study using the same technique started in August 2018 for people with Acute Lymphoblastic Leukaemia.

Over the past three years scientists in China have used newer versions of CRISPR to genetically engineer cells of at least 86 cancer and HIV patients. These cases form part of eleven human clinical studies using CRISPR-Cas9 technologies, ten of which are being undertaken in China. Another development of CRISPR is ‘base-editing’, which chemically modifies rather than cuts DNA. An August 2018 edition of the journal Molecular Therapy, describes how scientists in China used base editing, to remodel the DNA of human embryos to treat patients with the Marfan syndrome, which is a relatively common inherited connective tissue disorder with significant morbidity and mortality. A further milestone for the technology was reported 2018 when a study, led by Zheng Hu of the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, China, was the first to edit human cells while inside the body in an attempt to eliminate the human papilloma virus, which is the main cause of cervical cancer.

Company activity and clinical studies

Since the first publications in 2012 showcasing CRISPR-Cas9 as a gene editing tool, a number of companies have been set up to leverage the technology to develop innovative therapies. For example, Editas Medicine, was founded in 2013 by Feng Zhang, Jennifer Doudna, David Liu, George Church, and J.Keith Joung. However, just a few weeks after the company’s formation, Doudna stopped all involvement with Editas after Zhang was granted a number of CRISPR patents and issues concerning intellectual property began to appear. In October 2018 Editas filed an Investigational New Drug (IND) application with the US Food and Drug Administration (FDA) for a clinical study of a CRISPR genome editing medicine called EDIT-101 for the treatment of Leber Congenital Amaurosis type 10 (LCA10). This is a serious eye disorder that affects the retina, which is the specialized tissue at the back of the eye that detects light and colour. People with LCA10 typically have severe visual impairment from infancy.

In 2018 the European Patent Office granted Cellectis, a French biopharmaceutical company, the first patent to use CRISPR technology in human T cells.The patent will protect the application of CRISPR gene editing for T cell research until 2034, meaning every other company employing similar systems will need a license from Cellectis. Also, in 2018 CRISPR Therapeutics, co-founded by Emmanuelle Charpentier began a clinical study using CRISPR genome editing technologies and a similar ex vivo approach to target the blood disorder β-thalassemia. As yet no CRISPR therapies have reached the clinic.

US-China competition

There is intense and growing scientific competition between the US and China. Although CRISPR was invented in the West, it is more rapidly being transformed in China into therapies that can be used in clinics. An article in a January 2018 edition of the Wall Street Journal suggests that regulation governing genome editing of human embryos in China is much less stringent than in the West where researchers have to pass muster with hospital review boards, ethics committees and government agencies before receiving approval. In China it is not unusual simply for hospital committees to give such permissions. According to Carl June, director of translational research at the Abramson Cancer Center, University of Pennsylvania and well-known for his research into T-cell therapies for the treatment of cancer, “We are at a dangerous point in losing our lead in biomedicine. It is hard to know what the ideal is between moving quickly and making sure patients are safe”. Western scientists believe that the less that stringent regulation in China gives Chinese researchers a significant competitive advantage in the race to get CRISPR therapies into clinics and bioethicists believe that loose regulation will result in unintended consequences that will harm patients and lead to “designer babies”, which could set-back the field for everyone.

Blurred line between therapy and enhancement

What makes regulation challenging is that CRISPR technologies blur the distinction between “therapy” and “enhancement”. Indeed, the 2018 Nuffield Council report referred to at the beginning of this Commentary suggests that such a distinction between therapy and enhancement cannot be expected to hold. Thus, it seems reasonable to assume that sometime in the future, CRISPR technologies, which are cheap, easy to use and accessible could be used to genetically enhance off-springs. In the first instance this solely might be focused on eradicating life-threatening diseases, but in the longer term it seems probable, especially in the absence of any universally agreed and tightly administered regulations, that genome editing will be used to create off-springs, which satisfy parents’ preferences for children with specific characteristics. Further, CRISPR technology is becoming popular among DIY scientists and biohackers – people who experiment on themselves - which exacerbates the concerns of bioethicists.

People have been radically altering bodies for millennia

Another reason to believe that germline editing will be used for ‘cosmetic’ enhancements rather than medical therapies is that for millennia people have used radical techniques to modify their own and their children’s bodies for cosmetic rather than therapeutic purposes. Here we illustrate the point with a few examples.

From the Song dynasties, which ruled China between 960 and 1279 until the early 20th century, the Chinese practiced the custom of breaking their first daughter’s toes and tightly binding them under the soles of their feet in order to stunt growth so that when the girl grew up she would walk diffidently, which was perceived as attractive. In England during the Victorian era between the mid 19^th and the beginning of the 20^th century, women, to make themselves attractive to men, corseted their bodies so tightly to create twelve-inch waists that their internal organs were redistributed with potentially dangerous consequences. Girls as young as 4 from the Kayan tribe of Myanmar use heavy brass coils to elongate their necks; a painful tradition dating back to the 11^th century. The brass coils, that weigh an average of 10 kilos, deform their collar bones and neck and shoulder muscles. The Mursi tribe in Africa cut the lower lips of girls and insert plates to stretch the lips up to 12 cm in diameter.

In the 1970s and 1980s elective cosmetic surgical procedures gained popularity among wealthy people on the East and West coasts of America in order to enhance their appearance. The trend soon became global through the explosion of mass media. According to the International Society of Aesthetic Plastic Surgery in 2017 there was a 9% overall annual increase in surgical and nonsurgical cosmetic procedures globally. The US was the leader, accounting for 17.9% of all procedures. The top five countries were the US, Brazil, Japan, Italy and Mexico, which together accounted for 41.4% of all cosmetic surgical procedures worldwide. Russia, India, Turkey, Germany and France completed the top ten countries. In 2017, 400,000 American women elected to have breasts augmentation surgery; a 41% increase since 2000. About 1m rhinoplasties are carried out each year, with high volumes in Brazil and Mexico. The International Society of Aesthetic Plastic Surgery also reported that in 2016 surgeons in South Korea carried out the most cosmetic surgical procedures per capita: 20 per 1,000 people. V-shaped chins, with minimal jaw or cheekbone, round skulls, lifted lip corners, petite lips and slight puffiness under the eyes have been popular surgeries in South Korea, but recently the demand for such procedures has decreased while simpler and less invasive surgeries have increased. The Society also reported that labiaplasty showed the biggest (45%) increase since 2015. Lower body lift procedures increased by 29%, while upper body lift, breast augmentation using fat transfer, and buttock lifts increased by some 20%.

Such examples suggest that body enhancements, using a range of techniques, have been practiced in many cultures throughout the world for millennia. Thus, it seems reasonable to assume that in the absence of stringent regulation CRISPR will be perceived by some as just another enhancement technique.

Takeaways

The discovery of CRISPR Cas9 has revolutionized the way we think about developing therapies for the world’s deadliest diseases. This powerful technology has significant advantages over traditional medical technologies; it is cheap, easy-to-use and accessible, and these factors have helped to drive CRISPR’s global acceptance and use as a tool for new and innovative therapies. Over the past three years CRISPR R&D and clinical studies have developed at a pace and bring huge promise and significant hope to millions of people living with conditions with high rates of morbidity and mortality. Notwithstanding, bioethicists warn that with the absence of stringent universally agreed regulation, all these advantages could easily pivot into significant disadvantages and lead to parents enhancing the genetic composition of their children to make them taller, more intelligent etc. This could be a small step away from reigniting the ‘Charles Galton movement’. Galton was an English scholar and cousin of Charles Darwin. He lived during the Victorian era and died in 1911. Among other things, Galton studied anthropology and sociology and suggested that the elevated social position and heightened intelligence of the English upper classes and the criminality and lack of intelligence of the English under classes were all inherited traits and the result of superior and inferior genetic make-up respectively. According to Galton societies could be improved by selective breeding. Bioethicists are concerned that CRISPR technologies could be used for a 21^st century version of Galtonism.

The genie is truly out of the bottle.

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CRISPR positioned to eliminate human papilloma viruses that cause cervical cancer

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HPV

HPV vaccination

Human Papilloma Virus

A 2018 clinical study in China is the first to use CRISPR to edit cells inside the human body in an attempt to eliminate the human papilloma virus (HPV) and is hugely significant for millions of women
Nearly all sexually active people get an HPV virus at some point in their lives and persistent high-risk HPV infections are the main cause of cervical cancer
Respectively 34,800 and 256,000 women in the UK and US live with cervical cancer and each year about 3,200 and 12,200 new cases of cervical cancer are diagnosed in the UK and US respectively nearly all related to HPV
Cervical cancer is increasing in older women not eligible for the HPV vaccine and not availing themselves of Pap test screening programs
A new study suggests that cervical cancer mortality among older women could increase by 150% in the next 20 years

CRISPR positioned to eliminate human papilloma viruses that cause cervical cancer

January 2018 marked the beginning of the first CRISPR clinical study to attempt to edit cells while they are in the body of women in the hope to eliminate the human papilloma virus (HPV), which is the main cause of cervical cancer. The study, led by Zheng Hu of the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, China, is the first to edit human cells while inside the body. Zheng Hu will apply a gel that carries the necessary DNA coding for the CRISPR machinery to the cervixes of 60 women between the ages of 18 and 50. The study’s aim is to prevent cervical cancers by targeting and destroying the HPV genes that cause tumor growth while leaving the DNA of normal cells untouched. Current estimates suggest that every year 527,624 women are diagnosed with cervical cancer and 265,672 die from the disease. Zheng Hu’s study is expected to be completed by November 2018 and findings reported in January 2019.

In this Commentary

This Commentary describes the Chinese CRISPR study and the etiology and epidemiology of cervical cancer. It also describes the current cervical cancer vaccination possibilities and the challenges they face. Further, the significance of the Chinese study is demonstrated by an English study, published in December 2017 in the Lancet Public Health, which warns that although HPV vaccination programs have significantly reduced the incidence of cervical cancer among young women, the incidence of the disease is increasing significantly among older women who do not qualify for the cervical cancer vaccine, and fail to avail themselves of regular Pap tests (A Pap test is a simple, quick and essentially painless screening procedure for cancer or precancer of the uterine cervix). The latter part of the Commentary describes advances that CRISPR technology has made over the past decade as well as describing its main ethical and technical challenges.

Human papilloma virus (HPV)

There are over 200 different types of HPV related viruses. Viruses are the etiological agents of approximately 15% of human cancers worldwide, and high-risk HPVs are responsible for nearly 5% of cancers worldwide. It is estimated that about 75% of the reproductive-age population has been infected with 1 or 2 types of genital HPV. About 79m Americans are currently infected with HPV, and about 14m people become newly infected each year. The American Centers for Disease Control and Prevention estimates that more than 90 and 80% of sexually active American men and women respectively will be infected with at least one type of HPV at some point in their lives. Most HPV infections are harmless, they last no more than 1 to 2 years, and usually the body clears the infections on its own. More than 40 HPV types can be easily spread by anal, oral and vaginal sex. About 12 HPV types are high risk, and it is estimated these persist in only about 1% of women. However, a central component of the association between HPV and cervical carcinogenesis is the ability of HPV to persist in the lower genital tract for long periods without being cleared. These persistent high-risk types of HPV can lead to cell changes, which if untreated, may progress to cancer. Other HPV types are responsible for genital warts, which are not sexually transmitted.

Etiology of cervical cancer

“The way that the HPV causes cancer informs us about how cancer occurs in other settings. Virus particles insert foreign DNA into a person’s normal cells. This virus then turns off the “off-switch” and allows the oncogenes [Genes that can transform a cell into a tumor cell] to progress unchecked and create an oncogenic virus. So, in this case the 'insult' is known: it’s an HPV virus. However, in many circumstances we’re not sure what that initial switch is that upsets the balance between a tumor suppressor and an oncogene,” says Whitfield Growdon, of the Massachusetts General Hospital and Professor of Obstetrics, Gynecology and Reproductive Biology at the Harvard University Medical School: see video below:

HPV and cervical cancer

The association of risk with sexual behavior has been suggested since the mid-19^th century, but the central causal role of HPV infection was identified just 40 years ago. HPV infection is the main etiologic agent of cervical cancer. 99% of cervical cancer cases are linked to genital infection with HPV and it is the most common viral infection of the reproductive tract. HPV types 16 and 18 are responsible for about 70% of all cervical cancer cases worldwide. Further, there is growing evidence to suggest that HPV also is a relevant factor in other anogenital cancers (anus, penis, vagina and vulva) as well as head and neck cancers. The importance of prevention and cervical cytological screening was established in the second half of the 20^th century, which preceded and even advanced etiologic understanding.

Epidemiology of cervical cancer

Cervical cancer is one of the most common types of gynecological malignancies worldwide. It ranks as the 4th most frequent cancer among women in the World, and the 2nd most common female cancer in women between 15 and 44. According to the World Health Organization there were some 630m cases of HPV infections in 2012, and 190m of these led to over 0.5m new diagnoses of cervical cancer. The World has a population of some 2,784m women aged 15 and older who are at risk of developing cervical cancer. Each year about 3,200 and 12,200 new cases of cervical cancer are diagnosed in the UK and US respectively; nearly all related to HPV. There is estimated to be 34,800 and 256,000 women in the UK and US respectively living with cervical cancer. Each year some 890 and 4,200 women die from cervical in the UK and US respectively.

HPV vaccines

HPV vaccines, which prevent certain types of HPV infections, are now available to females up to the age of 26, and have the potential to reduce the incidence of cervical and other anogenital cancers. “Vaccinations work by using your own immune system against foreign pathogens such as viruses and bacteria. Vaccination against some high risk sub-types of cancer-causing HPV viruses is one of the most meaningful interventions we’ve had since the development of the Pap test,” says Growdon: see video below.

Gardasil and Cervarix

Gardasil, an HPV vaccine developed by Merck & Co., and licenced by the US Food and Drug Administration (FDA) in 2006, was the first HPV vaccine recommended for girls before their 15th birthday, and can also be used for boys. In 2008 Cervarix, an HPV vaccine manufactured by GlaxoSmithKline, was introduced into the UK’s national immunization program for girls between 12 and 13. Both vaccines have very high efficacy and are equally effective to immunise against HPV types 16 and 18, which are estimated to cause 70% of cervical cancer cases. Both vaccines significantly improve the outlook for cervical cancer among women living in countries where it is routinely administered to girls before they become sexually active. “Both Gardasil and Cervarix vaccines have been shown to be incredibly effective at preventing the development of high-grade dysplasia, which we know, if left unchecked, would turn into cervical cancer,” says Growdon: see video above.

Gardasil also protects against HPV types 6 and 11, which can cause genital warts in both men and women. Second-generation vaccines are under development to broaden protection against HPV. In 2014 the FDA approved Gardasil 9, an enhanced vaccine, which adds protection against an additional 5 HPV types that cause approximately 20% of cervical cancers.

Global challenge

Despite the availability of prophylactic vaccines, HPVs remain a major global health challenge due to inadequate vaccine availability and vaccination coverage. Despite the promise, vaccine uptake has been variable in developed nations, and limited in developing nations, which are most in need. The available vaccines are expensive, require a cold chain to protect their quality, and are administered in 2 to 3 doses spanning several months. Thus, for a variety of practical and societal reasons (e.g., opposition to vaccination of young girls against a sexually transmitted agent, fear of vaccination), coverage, particularly in the US has been lower than would be optimal from a public health perspective.

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Gene editing battles

Success among young women

Notwithstanding, a study referred to above and published in the Lancet Public Health suggests cervical cancer cases are expected to fall by 75% among young women for whom vaccination is now the norm. Death from cervical cancer among the generation who were 17 or younger in 2008 when the UK vaccination program was introduced is expected to virtually disappear.

Challenges for older women

Notwithstanding the success of HPV vaccines for young women, there are continuing challenges for older women who, because of their age, do not qualify for HPV vaccines, and do not attend their Pap screening test when invited. “Pap tests involve scraping the cervix on the outside for cells, which then udergo microscopic examination. Today this is carried out by a computer. Further examination is carried out by a cytopathologist who determines status . . . . . . . . . . Pap tests do not diagnose cancer, but tell you whether you are at high risk of either having pre-cancerous or cancerous cells. Actual diagnosis of cervical cancer involves a colposcopy. This is a simple procedure, which uses a specific type of microscope called a colposcope to look directly into the cervix, magnify its appearance, and helps to take biopsies of abnormal areas,” says Growdon: see videos below.

What is a Pap smear test?

Diagnostic tests for cervical cancer

Older women and Pap tests

Pap tests, which are offered by NHS England to women between 25 and 64, is the most effective way of preventing cervical cancer; yet data show that in 2016 there was a significant drop in Pap test screening as women’s age increased. If such screening covered 85% of women, it is estimated that it would reduce deaths from cervical cancer by 27% in 5 years, and the diagnosis of new cases of cervical cancer by 14% in 1 year. According to the authors of the 2017 Lancet study, “The risk of acquiring an HPV infection that will progress to cancer has increased in unvaccinated individuals born since 1960, suggesting that current screening coverage is not sufficient to maintain – much less reduce – cervical cancer incidence in the next 20 years.”

Cervical cancer projected to increase in older women

Over the next 2 decades, diagnoses of cervical cancer in women between 50 and 64 are projected to increase by 62%, which could increase mortality from the disease by nearly 150%. “The main reason for this is that the population is ageing and women currently 25-40 will not benefit from vaccination – and they are in the age range where the likelihood of getting an HPV infection is quite high,” saidAlejandra Castanon one of the authors of the Lancet study.

Chinese study extends CRISPR technology

The Chinese study mentioned above to eliminate the HPV virus employs an innovative extension of CRISPR, which is a ‘game-changing’ technology. Over the past decade CRISPR has become a significant tool for genetic manipulation in biomedical research and biotechnology.

CRISPR and genome editing

CRISPR is a complex system that can recognize and cut DNA sequences in order to provide organisms a strong defence against attacks and make them immune from further assaults. CRISPR has been adapted for both in vitro and in vivo use in eukaryotic cells to perform highly selective gene silencing or editing. Eukaryotic cells are those that contain a nucleus surrounded by a membrane and whose DNA is bound together by proteins into chromosomes. CRISPRs are specialized stretches of DNA, and "CRISPR-Cas9" provides a powerful tool for precision editing due to its highly efficient targeting of specific DNA sequences in a genome, and has become the standard for genetic editing. Cas9 protein is an enzyme that acts like a pair of molecular scissors capable of cutting strands of DNA. The genomes of organisms encode messages and instructions within their DNA sequences. Genome editing involves changing those sequences, thereby changing the messages. This is achieved by making a break in the DNA, and tricking a cell's natural DNA repair mechanisms to make desired changes; CRISPR-Cas9 provides a means to do this. The technology’s ease of use and low cost have made it popular among the scientific community, and the possibility of its use as a clinical treatment in several genetically derived pathologies has rapidly spread its significance worldwide.

Changing ethical concerns

Despite CRISPRS promise there have been significant ethical concerns to genome editing, which center around human germline editing. This is because germline editing entails deliberately changing the genes passed on to children and future generations; in other words, creating genetically modified people. The debate about genome editing is not a new one, but has regained attention following the discovery that CRISPR has the potential to make such editing more accurate and even "easy" in comparison to older technologies. As of 2014, there were about 40 countries that discouraged or banned research on germline editing, including 15 nations in Western Europe. There is also an international effort, launched in December 2015 at the International Summit on Human Gene Editing and led by the US, UK, and China, to harmonize regulation of the application of genome editing technologies.

After initially being opposed to using CRISPR in humans, in June 2016, the US National Institutes of Health advisory panel approved the technology for a study designed to target three types of cancer and funded by the Parker Institute for Cancer Immunotherapy at the University of Pennsylvania. In 2017 the UK approved the use of CRISPR for research in healthy human embryos.

Off-target effects

Soon after scientists reported that CRISPR can edit DNA in 2012, experts raised concerns about “off-target effects,” meaning either CRISPR changes a gene scientist did not want changed or it fails to change a gene that they do. Although CRISPR-Cas9 is known for its precision a study, published in 2017 in the journal Nature Methods, raised concerns that because of the potential for “off-target effects” testing CRISPR in humans may be premature. Non-intended consequenes can happen because one molecule in the CRISPR system acts like a “molecular bloodhound”, searching the genome until it finds a match to its own sequence of genetic letters; but there are 6bn genetic letters of the human genome, which suggests that there may be more than one match. Scientists anticipate and plan for this by using a computer algorithm to predict where such flaws might occur, then they search those areas to see if such off-target effects did occur. Notwithstanding such procedures and despite CRISPR’s precision, substantial efforts still are required to make the technology a common device safe for human clinical treatments.

Advances using CRISPR

The first clinical study using CRISPR began in October 2016 at the West China Hospital in Chengdu. Researchers, led by oncologist Lu You from Sichuan University, removed immune cells from the blood of a person with lung cancer, used CRISPR to disable a gene called PD-1, and then returned the cells to the body. This study is part of a much larger CRISPR genome editing revolution. Today, there are about 20 human clinical studies taking place using CRISPR technology most of which are in China. Different studies focus on different cancers including, breast, bladder, oesophageal, kidney, and prostate cancers. Further, a 2017 paper published in the journal Cell describes a number of innovative ways CRISPR being used; including editing cells while inside the body.

Takeaways

Despite the efficacy of HPV vaccines, immunization against cervical cancer still has significant challenges. Vaccines only target young people before they become sexually active, and are not recommended for slightly older and sexually active women. There is an urgent and growing concern about older women therefore who were not eligible for HPV vaccination, and are not availing themselves of regular Pap tests, and in whom the incidence of cervical cancer is increasing significantly. This makes Zheng Hu’s clinical study extremely important because it holds out the potential to substantially dent this large and rapidly increasing burden of cervical cancer.

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