4 May 2015
The Director of the US National Institutes of Health (NIH), Dr Francis Collins, has made a formal statement to the effect that the NIH will not fund any research involving the use of genome editing in human embryos.
Recent news of the first published example of the use of the innovative and highly promising technique of gene editing in (non-viable) human embryos by Chinese researchers has provoked widespread debate, and a significant (but far from unanimous) degree of condemnation from other researchers.
In the statement, Collins notes that altering the human germline in embryos, even for clinical reasons, ‘has been viewed almost universally as a line that should not be crossed’. They note that despite the ‘elegant’ new method for genome editing, strong arguments against use in humans remain, including ‘serious and unquantifiable safety issues’ as well as ethical barriers and a lack of medical applications that might justify its use.
Preimplantation genetic diagnosis (PGD) is a technique based on in vitro fertilisation (IVF) is already widely used in families affected by severe genetic diseases to prevent the birth of affected children; it involves the testing and selection of only healthy embryos for implantation in the mother. As stem-cell biologist Dr Paul Knoepfler observes: “In a match up of say CRISPR versus PGD, PGD would win almost 100% of the time as by far the best choice to tackle genetic disease”. Similarly, Dr Marcy Darnovsky of the Center for Genetics and Society told the BBC: "There is no persuasive medical reason to manipulate the human germline because inherited genetic diseases can be prevented using embryo screening techniques, among other means”.
The NIH statement goes on to outline some of the ‘multiple existing legislative and regulatory prohibitions’ against human embryo modification. These include the Dickey-Wicker amendment, a legal prohibition on the use of government funds for research that involves the creation or destruction of human embryos. This provided a hurdle to funding for some forms of human embryonic stem (HES) cell research in the US; it was invoked resulting in a temporary freeze in research funding in a legal challenge to President Barack Obama’s 2009 decision to lift earlier restrictions on federal funding for HES cell research.
Finally, the statement also notes that the Food and Drug Administration (FDA) holds regulatory authority over any form of human germline modification procedures in the US, federally or privately funded. Legal and regulatory barriers aside, not everyone agrees with the NIH’s stance. Biologist Prof David Baltimore told Nature News: “I am not in favour of the NIH policy and I believe that the Chinese paper shows a responsible way to move forward”.
Writing in the Guardian, Oxford bioethicist Christopher Gyngell says that calls for an international ban on gene editing in human embryos are wrong, and that the technique should be embraced and develo ped responsibly. He adds: “Whoever first crosses the line to edited embryos will find a powerful new resource in the fight against disease. Like many resources there are risks associated with its use. Indeed the risks are very high. However ignoring the resource is also risky. We may needlessly subject future generations to an endless cycle of sufferi ng and disease”.