human embryos
A doctor is silhouetted as he walks past a poster showing images of the development of a human fetus at Italian fertility doctor Severino Antinori's private clinic in Rome, June 6, 2005. REUTERS/ALESSIA PIERDOMENICO

Human gene editing is perhaps one of the most, if not the most, divisive issue worldwide and in the United States. A recent survey of over 4,700 U.S. adults found that when it comes to the use of biomedical interventions, including gene editing in human babies to reduce risk of serious diseases, a substantial number (nearly 70 percent) of people are “very” or “somewhat” worried.

The survey, carried out by the Pew Research Center, laid bare the stark difference in opinion between the general public and the scientists, most of whom have spoken out in support of research in an area that's even more of an ethical, religious and scientific minefield — embryonic gene-editing.

In such a backdrop, and with the advent of the extremely powerful and efficient gene-editing tool CRISPR-Cas9, it has become imperative that the issue be faced head on. In order to do so, and to advance discussion and research on human gene-editing, an influential science advisory group in the U.S. has now published a comprehensive report on the science, ethics and governance of human genome editing.

The report, drafted by scientists at the National Academy of Sciences and the National Academy of Medicine, outlines three areas where human genome editing can be used — basic science research in labs; altering somatic, or non-reproductive, cells for purposes of treating or preventing disease; and altering an individual’s germline, or reproductive, cells to treat and prevent heritable disease.

The last one is the area most mired in controversy. In its report, the advisory group endorsed clinical trials using heritable germline editing only in cases where no “reasonable alternatives” are present, and restricted it to cases where doing so would prevent babies from inheriting genes that would cause “a serious disease or condition.”

Furthermore, the changes should ensure that the edited genes match those “associated with ordinary health.”

“The committee recommends that genome editing for purposes other than treatment or prevention of disease and disability should not proceed at this time, and that it is essential for these public discussions to precede any decisions about whether or how to pursue clinical trials of such applications,” the report said. “It is important to note that such concepts as ‘reasonable alternatives’ and ‘serious disease or condition’ embedded in these criteria are necessarily vague. Different societies will interpret these concepts in the context of their diverse historical, cultural, and social characteristics, taking into account input from their publics and their relevant regulatory authorities.”

This means that if you are one of those awaiting the advent of Brave New World-esque, “designer babies,” you’ll have to keep waiting.

“Because such technologies as CRISPR/Cas9 have made genome editing so efficient and precise, they have opened up possible applications that have until now been viewed as largely theoretical,” the authors of the report wrote. “Because genome editing is only beginning to transition from basic research to clinical research applications, now is the time to evaluate the full range of its possible uses in humans and consider how to advance and govern these scientific developments.”

The first report of the Crispr/Cas9 technique being applied to human embryos emerged in April 2015, when a team of Chinese scientists showed — through a partially successful experiment — that errors in the DNA that cause beta-thalassaemia, a life-threatening blood disorder, could be corrected through gene modification in early stage embryos. The study, published in the journal Protein and Cell, triggered widespread outcry, with opponents calling it a move toward a dystopian world populated by “designer babies.”

We have come a long way since then. Authorities not just in China, but even in the U.K. and Sweden, have since granted approval to genetically modify human embryos for the purpose of research.

In the U.S., however, research efforts have been stymied by a congressional ban on germline editing.

This is where the recommendations of the advisory group may play a crucial role. Researchers hope that the Academies’ imprimatur would finally open the door to research and clinical testing in the field of human germline editing.

“We say proceed with all due caution, but we don’t prohibit germline, after considerable discussion and debate,” Richard Hynes, a biologist at the Massachusetts Institute of Technology, and one of the authors of the report, told Washington Post. “We’re talking only about fixing diseases.”