WASHINGTON, D.C. — Worries about “designer babies” might obscure the threat of far more likely abuses from a fast-moving genetic engineering method, researchers warned Tuesday at an international scientific summit.
An era of elite athletes doping their genes with muscle-builders intended for the elderly, or of genetic treatments intended to boost cognition in Alzheimer’s patients infiltrating the business world, were among the abuses conjured up at the International Summit on Human Gene Editing.
Held at the U.S. National Academy of Sciences, and co-sponsored by science academies of China and the United Kingdom, the international summit this week features scientific and ethical presentations devoted to the brave, new world of genetic engineering promised by a new gene editing biotechnology called CRISPR. CRISPR, cribbed from bacterial genes, allows scientists to easily tinker with or remove DNA.
CRISPR led to the first genetic engineering of human embryos, reported in April by Chinese researchers who, after doing their initial experiments, imposed a temporary moratorium on it. In September, a British scientist asked for permission from the the United Kingdom’s Human Fertilisation and Embryology Authority (HFEA) to also attempt genetic modification of human embryos.
“Things are clearly moving very quickly and this deserves serious discussion,” said Jennifer Doudna of the University of California, Berkeley, who led the 2012 discovery of the gene editing method.
The summit came about because of deep concerns over the possibility of genetic tweaks to human embryos that would forever alter the “germline” DNA of babies in every cell of their bodies, including sperm and ovaries, with uncertain effects passed along to future generations.
But Harvard’s George Church said at the summit on Tuesday that worry about designer babies was overstated. The bigger risk, he suggested, is the use of this technology on so-called somatic cells, which are not passed on to offspring.
For example, Church said, this somatic editing could lead to gene doping in sports or of brain-boosting gene treatments, similar to abuse of stimulants in academia. “If we are going to worry about something in international competition, it will be somatic enhancement, not germline enhancement," he said.
Genetic tweaking in somatic cells is already happening in the medical realm. Researchers have applauded proposals to use CRISPR to treat diseases such as HIV, sickle cell anemia, and cancer, by editing the DNA inside of somatic cells in the blood. In March, Sangamo, one of at least three biotech firms pursuing gene editing of immune cells, launched a clinical trial that will tweak the genes of people with HIV.
Other meeting attendees echoed Church’s concerns. Bioethicist Insoo Hyun of Case Western Reserve University in Cleveland, Ohio, said that genetically engineered immune cell treatments (such as those helping with muscle wasting in AIDS or cancer patients) could get in the hands of athletes for illicit use. Stem cell researcher George Daley of Boston Children’s Hospital acknowledged this was “a real worry” tied to FDA rules that allow doctors to prescribe “off-label” uses for prescription drugs. “We may want stricter rules in this case,” he said.
The FDA has already established regulations for earlier gene therapies that have been tried in human patients, bioethicist Alta Charo of the University of Wisconsin said. While laws become rigid over time, she said, such agency rules may adapt to changing technologies more easily.
Another researcher at the summit, Jonathan Weissman of the University of California, San Francisco, suggested that gene editing might treat HIV, cancer, or other ailments without adding or removing DNA from cells in any way. Instead CRISPR can move around DNA markers that cells use to turn genes on and off.
He proposed giving people pills dosed with CRISPR proteins tuned in this way to deactivate a gene called CCR5 that makes people vulnerable to HIV, for example. Once they stop taking the pill, the gene would reactivate, obviating worries about permanent changes to genes.
Despite the progress in the field — illustrated by the journal Science releasing a paper on Tuesday reporting a way to improve the accuracy of CRISPR edits — scientists such as Nobel Prize Winner David Baltimore of Caltech cautioned that the basic biology of CRISPR needs more work before any of the promised benefits or worries will come true.
“The whole simplicity of the method is a little overhyped,” Baltimore said. “It’s not really something you can do in a garage.”
Jennifer Doudna works at the University of California, Berkeley. An earlier version of this post misstated her institutional affiliation.