Friday, October 4, 2019

TOWARD RESPONSIBLE HUMAN GENOME EDITS


 Are we ready to perform genome edits?  Hynes et al have written a commentary in JAMA 

 Genome editing (link) which discusses this procedure.
See also
Nature series
 Editing ethics

The procedure is in its very early stages but already raises major issues of bioethics.

Enhancement:  "A controversial aspect of genome editing concerns its potential use for modifying physical traits and capacities beyond those typical of adequate health. For example, using somatic genome editing to improve musculature in patients with muscular dystrophy would be considered a restorative treatment, whereas using the same intervention for individuals with no known pathology and average capabilities would be considered “enhancement.” Currently, the potential benefits of applications for enhancement are unlikely to outweigh the risks, and the report recommends that such uses should not be approved at this time. With additional research, risks will probably diminish, and it will become increasingly important to have public engagement and input on howto weigh the purported benefit of any enhancement against risks and to explore the social implications, both real and feared, as governance policies develop."
Science fiction stories about spies with super-powers already clog the media.  And athletics has been plagued by biological manipulations of hormones, etc to improve athletic performance.  The idea of doing this procedure to produce a cadre of warriors or athletes is concerning,  as well as the implication that only some of the edits would be useful and the other manipulated individuals "wasted" with no realistic consent.

 Editing for Treatment or Prevention of Disease or Disability
"A ... potential application of human genome editing involves alteration of germ line cells to prevent serious disease or disability. Germ line editing has been conducted successfully in animals, but major technical issues must be overcome to use this in humans."
Although this procedure seems morally more straightforward,  it is based on the assumption that one or a small number of edits to defective alleles would produce significant change.  Diseases with single locus dominant or recessive features exist but are much rarer than the broad categories of diabetes, heart disease, hypertension, etc that represent the major sources of illness,  and are polygenetic.  This focuses the value on a small number of instances with high cost and challenges.  And it does not address the other potential role of these alleles and how altering them might be detrimental.


"Nonetheless, this line of research is of interest because there are thousands of inherited diseases caused by mutations in single genes. When no other reasonable alternatives are available, editing germ line cells could reduce the burden of disease for a child and allow prospective parents to have genetically related offspring without the risk of transmitting disease-causing mutations to their children. Because germ line editing would result in genetic changes that could be inherited by the next generation, it raises greater concerns about safety, informed consent, and unintended effects. It has also been argued that germ line gene editing crosses an ethical line, and there are concerns about equity of access and the potential effect on individuals with disabilities. Given these technical and societal concerns, the committee concludes that there is need for caution in any move toward germ line editing, but that caution does not mean prohibition."


"Although one day it may be technically safe to use genome editing for enhancement, societies, professional organizations, and governmental agencies still may choose not to approve such applications because they violate certain core principles such as respect for persons, equity, and fairness. Moreover, it is important to emphasize that many of the traits, such as intelligence, that are commonly discussed in the media as potential targets for enhancement, are complex and thus very unlikely to be readily modified by genome editing."

"The report recommends that clinical trials of germ line editing might become permissible but only after
much more research to meet appropriate risk/benefit standards for authorizing such trials.Even then, germline editing should be permitted only for compelling reasons and under strict oversight. In the United States, authorities are currently unable to consider proposals for this clinical research because of a prohibition on use of federal funds by the US Food and Drug Administration to review “research in which a human embryo is intentionally created or modified to include a heritable genetic modification.” Similar prohibitions exist in many other countries. There is a risk that if established bodies are not permitted to regulate this field, it might develop outside societal norms, leading to applications that are not scientifically valid or that violate core ethical principles. The committee defined a set of stringent criteria under which heritable germ line editing might be permissible if US restrictions are lifted
or if countries without legal prohibitions proceed with this line of research.."


While a noble sentiment, this report fails to acknowledge that the economic, military, and political advantage will drive the research despite ethical concerns,  as it drove cloning animals and eventually reportedly a human infant.  This procedure may be added to the list of proliferation of nuclear weapons, "hacking into vital infrastructure systems", "exploitation of outer space", and the other scientific boundaries of development which the earth as a unified political has so far been unable to join together to manage and regulate safely.

"Urging public education and engagement to assess and apply societal values to the risks and benefits of genome editing technologies disregards the powerful drive of money and power to overwhelm public boundaries. For somatic genome editing for treatment of disease, the Recombinant DNA Advisory Committee currently provides a forum for public engagement. While the report recommends against using somatic cell editing for enhancement at present, continued transparent and inclusive public engagement and education through multiple forums are needed to assess whether there is evolution of societal views on this issue over time. With respect to heritable germ line editing, broad participation and input by the public, along with ongoing reassessment of both health and societal benefits and risks, should be a precondition for moving any clinical trials forward."

The example of genetically modified foods is an example of the failure of public opinion as a regulatory process.  The development of these foods to enhance potability and ease production has potential value.  The complex risks in the genetic engagement of these altered species with non-altered crops remains unresearched because it has no financial value to the producing companies.  Their only concern is to prevent cross-pollination of their patented crops.  Concerns about the impact of consumption of these products is also speculative.  Short term trials do not indicate immediate negative effects of consumption,  but food is consumed for a lifetime, and so the long term potential of these modifications will only be understood by complex, expensive population studies which will be opposed and hampered whenever possible by the producers until the patents run out.

"The thrust of the report’s recommendations is to maximize the benefits to human health of any applications of genome editing. While heritable germ line editing is currently not feasible and probably will not be for several years, it is possible to foresee paths whereby it may become a realistic possibility. It is incumbent on society to take advantage of the opportunity to promote public engagement on the societal issues to inform regulatory decisions if and when that possibility becomes a reality. The committee’s recommendations on heritable germ line editing constitute a progression from the category of “never” to the category of “maybe, but only if …” but with no applications for enhancement—the goal would be healthy infants, not “designer babies.”"

It is hard to imagine a more naive, unfortunate assessment of the risks and complexities of this profound process, and that it's exploitation will be accelerated unless major world intervention at the level of managing biological or nuclear weapons is arranged.  (We are not so great at managing them either.)