embryo editing against disease is unsafe and is not proven
The Impact of Multiplex Genome Editing on Hereditable Embryo Development and the Prevalence of Multiple Delayed Types of Diseases
S.C. is supported by a research grant from the National Human Genome Research Institute of the National Institutes of Health (grant no. The consultant is a paid consultant and holds stock options at MyHeritage.
The possibility of editing the genomes of human embryos has been widely discussed, particularly since the discovery of the CRISPR–Cas9 gene-editing tool. The revelation in late 2018 that a Chinese scientist, He Jiankui, had edited embryos that became living babies created a huge wave of controversy1. Writing in Nature, Visscher et al.2 describe a mathematical model that argues that just a handful of edits could reduce the risk of various disorders dramatically — in a theoretical scenario in which heritable, large-scale genome editing is feasible and safe. Despite the claims being logical and thought- provoking, the model the authors use is dependent on several assumptions and ignores serious risks. The work might have a big effect on policy given the broad interest. It raises both scientific and ethical issues, which we discuss here.
Gene-editing tools currently in development, called multiplex technologies, are projected in the coming decades to enable rapid precision DNA editing at tens, or even hundreds, of locations. The researchers found that, in some cases, editing a single variant associated with a polygenic disease can have strong effects, and, with the exception of MDD, editing up to ten genes associated with a disease can reduce its lifetime prevalence by an order of magnitude.
Peter Visscher, a statistician and geneticist at the University of Queensland, Australia, and his colleagues modelled the consequences of simultaneously editing specific variants linked to a number of diseases, including Alzheimer’s disease, schizophrenia, type 2 diabetes, coronary artery disease and major depressive disorder (MDD).
Researchers from Australia, China and the US have examined the possibility of editing genomes of human embryos in the future. They found that in some cases, editing a single variant associated with a polygenic disease can have strong effects and that editing up to ten genes associated with a disease can reduce its lifetime prevalence by an order of magnitude.