Cautious approach warranted for new gene-editing technique

Orange County Register

A new genetic-modification technology proven to be quicker and cheaper than past methods of altering DNA in plants and animals has been approved to modify human embryos for research in England. In theory, this could correct gene mutations that lead to disease and death, but the reality is that the gene-editing technique could catalyze a new eugenics, if the thin line is crossed from targeting disease to human enhancement.

Known as CRISPR, an acronym for Clustered Regularly Interspaced Short Palindromic Repeats, researchers using it have been able to genetically modify a whole host of plants and animals in record time.

The most audacious idea is to use the gene-editing technique to create designer babies with enhanced traits. Some want to forge ahead quickly, but I don’t think we are ready.

This month, the Human Fertilization and Embryology Authority, a regulatory body in England, gave a researcher there the green light to modify human embryos for research. Last week, the National Academy of Sciences held its second meeting on human genetic modification. After its first meeting in December, I was disappointed that the organizers didn’t impose a moratorium on using the technique to modify people.

In the laboratory, we push the boundaries of science to find out what’s possible, what we can do. We don’t think about what we should do. With transformative technologies like CRISPR, scientists have a special responsibility to flip the equation to, “Should we do that?” The public needs to be part of answering that question at least in part because scientists, myself included, have gone a bit crazy with this new gene-editing technique.

CRISPR is a sort of turbocharged genetic Swiss army knife. It pinpoints specific genes, cuts them and then rewrites their DNA as the cuts are fixed.

In 2015, researchers using the technique created double-muscled pigs and buff beagles, by modifying a gene called myostatin. Remarkably, some now want to modify myostatin in people. Another team created micro pigs to be sold as tiny pets.

More serious uses in people could reverse mutations that cause blindness, change cells to resist HIV, and provide new avenues to other serious illnesses such as cystic fibrosis. These are very exciting possibilities, but can humanity avoid using it in a eugenic way to try to make “better” people with big muscles, unusual eye color or other enhancements? Another risk is that the gene-editing technique can make mistakes in rewriting DNA that could cause disease.

Would doing so be legal? A last-minute rider was added to the 2016 federal budget barring the FDA from considering applications to modify genes in humans. Still that provision is only temporary and wouldn’t necessarily apply to all privately funded efforts. There is such great interest in the technique – billions from investors and attention from Google, Bill Gates, and others – that I seriously doubt the FDA can keep up.

The breathless talk today of modifying the genes of people could be extremely dangerous.

To be clear, as a scientist I’m a big fan of CRISPR, and the research team of scientists in my lab at UC Davis uses it to study human stem cells and cancer cells, but only in dishes in the lab. We urgently need at least a temporary moratorium on using the gene-modification technology on people. We need to have a full public debate while we learn more about its potential positive and negative effects on humans.

Paul Knoepfler is an associate professor at the School of Medicine of UC Davis. He blogs at and can be found on Twitter @pknoepfler.