CRISPR Dangers Highlight the Need for Continued Research on Human Gene Editing

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This post is a part of our Bioethics in the News series

By Jennifer Carter-Johnson, PhD, JD

The excitement and potential of CRISPR to treat severe genetic conditions by editing disease-causing DNA has taken an unexpected hit. A recent Wall Street Journal article highlighted the unexpected results from a CRISPR study in which attempts to edit a human gene responsible for blindness resulted in the loss of the entire chromosome from the cells in the embryos. These results echo another study conducted in human cell lines published earlier in 2019.

CRISPR is a targeted gene editing process that allows scientists to direct genetic modifications with far more precision than prior procedures. CRISPR has been touted as a gigantic leap in the ability to modify DNA by creating or repairing pinpoint DNA mutations without affecting other areas of the chromosome on which the gene resides. The recent study indicates that the technique might not be as straightforward in humans – and thus neither will be its use to fight disease.

Blue DNA double helix puzzle with missing pieces
Image description: A partially assembled puzzle that is an image of blue double helix DNA molecule structures. Image source: Arek Socha/Pixabay

CRISPR Technology – Promise and Problems

The value in CRISPR mediated genetic modification can be seen in a wide variety of biotechnology products, such as genetically modified crops and new biologics. But perhaps the most exciting and most controversial potential for CRISPR can be found in the desire to modify embryonic genomes to remove genetic abnormalities for which we currently have no cure.

This promise of embryonic gene editing is appealing not only because it would remove the condition from the child born from the gene-edited embryo, but also because the offspring of that child would also be free of the condition. CRISPR gene editing – because it is done at the embryonic stage – creates germline mutations that are passed to future generations. In a therapeutic use of CRISPR, those mutations would be cures for often untreatable diseases.

However, it is this very promise that raises many of the problems with CRISPR embryonic gene editing. Much debate has surrounded embryonic gene editing. Until this recent news, there were fears that CRISPR may make gene editing too easy. The technological development of CRISPR in embryonic gene editing is moving at a breakneck pace as scientists around the world are working on procedures. Biohackers work in their garages and livestream the use of CRISPR to edit their own genomes.

Many are debating which genes should be targeted and how fast the research into actual trials should proceed. Most agree that severe diseases would be the best place to start, but should the technology be deployed for cosmetic benefits such as eye color, or diseases for which a treatment exists? The dangers of CRISPR editing are unclear, and there has been an informal moratorium on the use of the technology to create children. Despite that, there has been at least one rogue scientist who has created genetically modified embryos and brought them to full term birth.

International Policy on Human Gene Editing

The scientific research is not occurring in a vacuum. Each country decides how CRISPR can be used in its medical system – both when the technique is safe enough and on which diseases it should be used.

An international commission recently pronounced that the technology is not ready for clinic implementation because scientists don’t understand the full safety issues surrounding its use in human embryos. The commission described some of the potential clinical uses in the future and outlined a basic safety protocol for approval.

One of the creators of CRISPR, Jennifer Doudna, has also spoken out against applying CRISPR too hastily to embryonic gene editing. 

Based on the recent studies showing loss of chromosomes, the international commission and other scientists are correct to call for a moratorium on clinical embryonic gene editing.

Blue and green DNA double helixes and binary code
Image description: An abstract image of blue and green double helix structures and binary code (zeros and ones) against a black background. Image source: Gerd Altmann/Pixabay

CRISPR – The Path Forward

The setback in CRISPR gene editing does not mean that the technology and research should be discarded. The potential to change lives is too great; however, the dangers of use with our current understanding are even greater. So how do we move forward with CRISPR in embryonic gene editing? The answer must include balance – in research strategies and in voices.

While the technology is not ready for clinical use, and we have not yet determined which uses would be appropriate if it were available, the science should not stand still. The research surrounding CRISPR gene editing will yield insights into human biology that we cannot predict. For example, the loss of chromosome length in human embryonic cells undergoing CRISPR treatment seems to be different than the response of other species of embryonic cells. And debates about the appropriate use of the technology will allow us to discover more about ourselves as humans. 

As we debate the best way to develop and deploy CRISPR technology, we should look to a variety of stakeholders. Scientists have a solid track record in understanding when recombinant DNA technology has potentially hazardous implications. In the 1970s, the Asilomar Conference allowed scientists to put together research guidelines that allowed the technology to be developed without harming public health. In fact, the international scientific consensus not to use the technology such as described above indicates that scientists are beginning that work. Such a moratorium on clinical uses gives us time to understand how to deploy the technology in the safest manner.

Additionally, there is a role for the voices of the patients whose lives could be changed by the technology. Patients may not be in the best place to judge when the technology should be deemed safe enough to deploy, but they certainly will have input about which mutations cause hardships that merit the risk of germline editing. Many of these patients already work with scientists on potential treatments for their diseases. CRISPR discussions may open another avenue for many.

Finally, there is a role for legal regulation of the use of CRISPR. Governments should listen to the voices of scientists and potential patients in drafting these regulations. But as shown by the example of at least one rogue scientist, there needs to be teeth to the moratorium on CRISPR clinical use at this time. CRISPR and its use in human gene editing raise complicated issues and hold great promise as a powerful tool to defeat genetic diseases. The development of those technologies will not be straightforward or without risk and will require more basic science research to achieve clinical efficacy. But with proper planning, we may learn more about ourselves as humans on the path to a cure.

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Jennifer Carter-Johnson, PhD, JD, is Associate Dean for Academic Affairs and Associate Professor of Law in the Michigan State University College of Law. Dr. Carter-Johnson is a member of the Michigan State Bar. She is registered to practice before the U.S. Patent and Trademark Office.

Join the discussion! Your comments and responses to this commentary are welcomed. The author will respond to all comments made by Tuesday, December 15, 2020. With your participation, we hope to create discussions rich with insights from diverse perspectives.

You must provide your name and email address to leave a comment. Your email address will not be made public.

More Bioethics in the News from Dr. Carter-Johnson: Biohacking: How a DIY Approach to Biology Can Shape Our FutureWeb of Interests Surrounding Medicines Makes Patient Access Increasingly DifficultHumanity in the Age of Genetic ModificationDefining The Spectrum of “Normal”: What is a Disease?Dawn of False Hope: Spread of “Right To Try” Laws across the U.S.

Continue reading “CRISPR Dangers Highlight the Need for Continued Research on Human Gene Editing”

Defining The Spectrum of “Normal”: What is a Disease?

Bioethics-in-the-News-logoThis post is a part of our Bioethics in the News series

By Jennifer Carter-Johnson, JD, PhD

The world of Gattaca once seemed a faraway place where some babies had genetic defects corrected before birth resulting in two classes within society. However, a recent report that a Swedish scientist, Fredrik Lanner, has begun to edit the genome of healthy embryos has made the movie seem ever more probable. This report follows on the heels of reports from China that two teams have edited non-viable embryos to correct for a blood disease and to make the embryos more resistant to HIV infection. Embryo gene editing experiments have also been approved in the UK, and while the U.S. National Institutes of Health refuse to fund such experiments, some state funding agencies are beginning to consider it. The eventual goal of these experiments is to correct genetic diseases at conception, saving people from living lives with Huntington’s disease or with genetic predispositions for heart disease or breast cancer.

Part of the DNA sequences from the human genome
Image description: a page of a book displays part of the DNA sequences from the human genome. Image source: Flickr Creative Commons.

There are a myriad of concerns connected with the editing of human embryos as discussed in the reports mentioned above. Usage of embryos for any research is controversial since some believe that embryos should have rights equal to a born person. Beyond the basic question surrounding all embryonic research, scientists have questioned whether we should be creating designer babies, citing concerns that the use of embryo editing might inadvertently create new diseases. Additionally, access to the technology might be limited due to the high cost, giving rise to a situation where those who can afford to edit their child’s genome will have the advantages of selecting for children who are highly intelligent, highly athletic and low health risks. In a society where class inequalities are becoming ever more pronounced, use of embryo editing could exacerbate the problem by unevenly allocating not only resources but also abilities to those with money.

Perhaps one of the most difficult questions to be answered relates to which genes should be modified. As an abstract concept, using embryonic gene editing to cure a disease is more palatable to many than choosing eye color and height, but identifying a “disease” may be more complicated than it looks. As researchers identify the genetic basis for conditions that impact a person’s health, it forces us to ask if those conditions are diseases or merely a variation on the normal of human existence.

Some mutations that increase susceptibility to disease are actually beneficial mutations in the response to other diseases. The mutation that leads to sickle cell anemia protects against malaria in people who only have one copy of the mutation. Mutations in the T cell receptor CCR5 make a person more susceptible to psoriasis and infection by West Nile Virus but protect against HIV and smallpox infections. Obviously, we don’t know all the mutations that are beneficial against diseases, merely that some people get more or less sick when confronted with certain pathogens. It is possible that super-healthy, specifically-designed children would be ill-equipped to defend against an emerging disease where some members of a genetically diverse population would have protection.

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Image description: a bright blue frame surrounds an artist’s embroidered rendering of the human chromosome map. Image source: Flickr Creative Commons.

Other disease-causing genetic mutations may also shape traits that society views as a positive. For instance, some research links the genetic predisposition for bipolar disorder with high IQ and enhanced creativity. Would the individual or society benefit from ameliorating the former at the cost of decreasing intelligence and creativity? Conversely, if the intelligence and/or creativity are genetically linked to bipolar disorder, well-meaning parents, seeking to increase the potential of their child, may exacerbate a genetically related mental illness.

Finally, one person’s disease is another person’s normal, community and heritage. Deaf parents often resist cochlear implants in their deaf children. These parents don’t view deafness as a disability but rather a community with its own language and customs. This view stands in contrast to the views of many in the hearing community who view deafness as a defect to be cured. Indeed, most deaf people function well in both deaf and hearing areas of society. If embryonic gene editing became a norm, deafness might be “fixed” – a process that some in the deaf community would liken to genocide. Similarly, many in the autistic community refuse to define themselves as having a disease. Not too long ago, homosexuals were considered mentally ill, a view that has become anathema as research into and acceptance of alternate views of sexuality have grown. Understanding the genetic underpinnings of autism and homosexuality would open them to a similar debate about embryo editing.

Some variations from normal are not diseases, they are merely differences. Some diseases or predispositions to diseases mask a greater benefit to the person or to society as a whole under certain conditions. Still others are life threatening diseases that carry little to no benefit as compared to the harm. We don’t always recognize these alterations for what they are, which makes determining which genes to modify a very difficult task as embryo editing becomes more feasible.

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Jennifer Carter-Johnson, JD, PhD, is an Associate Professor of Law in the College of Law at Michigan State University. Dr. Carter-Johnson is a member of the Michigan State Bar and the Washington State Bar. She is registered to practice before the U.S. Patent and Trademark Office.

Join the discussion! Your comments and responses to this commentary are welcomed. The author will respond to all comments made by Thursday, November 3, 2016. With your participation, we hope to create discussions rich with insights from diverse perspectives.

You must provide your name and email address to leave a comment. Your email address will not be made public.

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Misconceptions: Ethics and the Rejection of Reproductive Roulette

Bioethics-in-the-News-logoThis post is a part of our Bioethics in the News series. For more information, click here.

By Leonard Fleck, Ph.D.

In a recent story in the New York Times, Gina Kolata reports the story of Amanda Kalinsky, age 30, who had been told four years ago that she had the gene for Gerstmann-Straussler-Scheinker [GSS] disease. This is a very rare neurological disorder that will result in a slow and terrible death, likely before she is fifty years old. Her father was dying of this disorder at that time. She very much wanted to have children but she could not bear the thought of passing on GSS to them. She had then learned of the option of pre-implantation genetic diagnosis [PGD]. This involved her being given a drug causing her to hyperovulate. Multiple ova would be surgically removed from her, inseminated by her husband, and result in the creation of 12 embryos. Over two days those embryos would grow to the eight-cell stage, at which point a cell would be removed from each and genetically analyzed for the GSS mutation. Six of her embryos had the GSS mutation. Those embryos were discarded. She successfully bore twins free of GSS and another child, also free of GSS. She and her husband paid over $20,000 for PGD.

Ethically speaking, how should individuals who wish to be just and caring and genetically responsible think about this procedure? How should citizens in a liberal, pluralistic society think about PGD? Should this be a covered benefit under the Affordable Care Act, at least for couples who know they are at risk of having a child with a serious genetic disorder that could very adversely affect the length or quality of life of a future possible child?

Advocates for a Right to Life position would surely object because the procedure necessarily involves the destruction of genetically flawed or excess embryos. They would further object to paying taxes to support access to the procedure for couples like the Kalinskys because this deeply violated their conscientious beliefs. The same is true for many advocates for persons with disabilities who regard this procedure as necessarily diminishing the value of persons with disabilities. Should we have a public policy that would ban this procedure, period?

Let me suggest two responses to the objections that have been raised. And let me also suggest why we should have a policy that would publicly subsidize the cost of the procedure for couples like the Kalinskys. First, what is being disvalued is the disability itself, not persons with disabilities. This can be understood more clearly with a brief thought experiment. Imagine that in the future regenerative medicine is able to use modified embryonic stem cells to restore mobility to individuals who have suffered severe spinal cord injuries. The cost of the procedure might be $100,000. I would argue that a just and caring society ought to underwrite that cost. Some persons with quadriplegia might refuse the procedure. Many others might gratefully accept it. There would be fewer immobile individuals in the world, but it surely seems that would be a good thing from the point of view of those newly mobile patients.

Advocates for a Right to Life position might argue that if a couple knows they are at risk for having a child with, say, cystic fibrosis, they ought either forego having children or accept having a child with cystic fibrosis. A child with cystic fibrosis may have lifetime medical costs in excess of $1 million, not to mention diminished length and quality of life. Those costs will largely be socially borne, as opposed to being borne by the parents. I would argue that the social acceptance of these costs is what a just and caring and liberally respectful society ought to do. However, others might see this a bit differently.

Others might regard such a couple as being thoughtless and irresponsible, both because of the preventable harm they are imposing on that child and the costs that are imposed on society. I would argue that such thoughts are illiberal. Those choices ought to be respected. But if that is true, then a liberal society is nothing if not mutually respectful. In other words, an advocate of a Right to Life position as well as advocates for persons with disabilities ought to respect the Kalinsky’s right to make their choice not to have children with GSS. Further, such advocates should also accept a democratically-legitimated policy that would pay the costs of PGD for couples like the Kalinskys, especially those not as economically well off as the Kalinskys. In both cases advocates for either point of view are paying taxes to support services they judge to be conscientiously troubling. But this is what mutual respect and fair treatment often means in a liberal pluralistic democratic society.

Perhaps I am wrong in my judgments here; perhaps advocates for a Right to Life position are wrong. If we both righteously insist on our rightness, then the practical consequence will be unnecessary suffering and premature death for many future possible children. Perhaps the better choice would be mutual respect and continued efforts at mutual understanding.

References:

Kolata, Gina. “Ethics Questions Arise as Genetic Testing of Embryos Increases.” New York Times 03 Feb 2014. Retrieved from http://www.nytimes.com/2014/02/04/health/ethics-questions-arise-as-genetic-testing-of-embryos-increases.html?hp&_r=3

Related reading:

Fleck smallLeonard Fleck, Ph.D., is a Professor in the Center for Ethics and Humanities in the Life Sciences at Michigan State University and the author of Just Caring: Health Care Rationing and Democratic Deliberation.

Join the discussion! Your comments and responses to this commentary are welcomed. The author will respond to all comments made by Thursday, March 6, 2014. With your participation, we hope to create discussions rich with insights from diverse perspectives. You must provide your name and email address to leave a comment. Your email address will not be made public.