The Ethical Issues Behind China’s CRISPR Twins
Earlier this week, a researcher announced the successful impregnation of a woman and birth of twin baby girls carrying CRISPR altered genomes, sparking global controversy
Sports legends like Usain Bolt, Lance Armstrong, and Michael Phelps were arguably born to be great athletes. Their genetic gifts effectively guaranteed that once they entered their chosen sport they would excel.
There are at least a handful of known genetic mutations, such as one in the ACTN3 gene that encodes a protein expressed in fast-twitch myofibres—the muscle fibers that respond on the rapid, forceful muscle contractions that occur in sprinting and weightlifting— that are clearly tied to above-average athletic abilities. The mutation is thought to also be associated with a lower risk of injury and adaptation to training regimens. Interestingly, like in the 2000 M. Night Shyamalan film “Unbroken,” and the upcoming January sequel “Glass,” the null variant, i.e., the total lack of the mutation, is associated with the exact opposite condition, increased susceptibility to muscle soreness and damage, as well as longer recovery times.
What if expecting parents, desiring that their future little Timmy become a sports sensation, employ innovative genetic tools like CRISPR, pronounced crisper, to alter the genome of their future child so that he carries the desired ACTN3 variant?
Would we feel differently if a similar set of parents employed the same technology to prevent a devastating congenital disease such as Tay Sachs, a disease so destructive that it effectively guarantees a painful life and death before the fifth birthday?
Some will see no ethical problem with either case, some will find fault with both, but most will have a hard time finding an objective red line that distinguishes between the first situation that they find viscerally troubling and the second scenario where they are empathetic to the parents and child.
Earlier this week, a Chinese researcher announced the successful impregnation of a woman and birth of twin baby girls carrying CRISPR altered genomes; if all goes well, the children are destined to carry a rare genetic mutation associated with some immunity to the HIV virus. A second pregnancy is also reportedly underway.
Where does this effort fall within the spectrum of undesirable to desirable genetic alterations? Ostensibly, the goal of the research was to help protect the two girls from becoming infected with HIV sometime later in life, but some have argued that the edits were unnecessary, given that there are other more straightforward, established and reliable ways to prevent the transmission of the AIDS virus.
CRISPR is an emergent technology, culled from an ancient natural defensive mechanism of bacteria and optimized for use in the targeted editing of genomes, in living cells within organisms. The technology has the ability to cut or insert a desired genetic sequence in the genome. Already subject to an intense patent battle, this technology is touted as the future of genetic engineering in humans given its relative ease-of-use and increased efficiency over previous editing tools.
The nearly universal outrage caused by the Chinese announcement, its veracity still unproven, relates to the generally accepted idea amongst ethicists that we should avoid germline engineering, a term referring to altering the human genome when that altered genome will be passed onto offspring, because we do not necessarily know, nor could we currently predict, all the unintended consequences of a germline edit, even a therapeutic one. Some have also argued, albeit more weakly, that it is manifestly unfair to alter the genetics of unborn offspring without their consent. Unlike germline manipulation, somatic cell engineering, which is more common in gene therapy, uses genetic tools that only affect the subject, not their future children.
Another concern with the Chinese effort relates to the general uncertainty and danger associated with employing these new CRISPR tools on people, particularly as, its unprecedented editing abilities notwithstanding, there remain concerns that the tool has unforeseen externalities particularly in its tendency to edit off-target areas of the genome.
Given all this, there have been calls for moratoriums on the use of CRISPR in viable human embryos. The National Academy of Sciences, a longstanding U.S.-based private organization consisting of respected scientists, established in 1863 as a result of an Act of Congress, has argued that CRISPR germline research on human embryos ought not be prohibited per se, rather limited to only serious diseases or clear unmet needs, but not what was reportedly done in China.
All of these efforts to limit CRISPR notwithstanding, history has proven that such efforts are usually in vain. Rogue scientists will always seek to circumvent any controls for well-intentioned, self-serving, or even malicious goals. As long as being first still carries substantial weight in science, it is unlikely that we can stop or slow down efforts in employing CRISPR.
Dov Greenbaum is a Director at the Zvi Meitar Institute for Legal Implications of Emerging Technologies, at Israeli academic institute IDC Herzliya. Meitar Bilu is a student at Zvi Meitar Institute.