Gene drive workshop shows technology’s promise, or peril, remains far off
By Elizabeth Pennisi
The idea sounds appealingly simple: Quickly spread a gene through a population of animals in order to prevent it from transmitting disease, or, more directly, to kill a destructive species such as an agricultural pest. But a workshop hosted yesterday by the National Academies of Sciences, Engineering, and Medicine (NAS) in Washington, D.C., made abundantly clear that a lot of uncertainty—scientific and regulatory—still exists for the so-called gene-drive technology at the heart of such concepts. And as result, field applications of gene drives are “still years off,” says Austin Burt, a population geneticist at Imperial College London who spoke at the meeting.
Over the past 3 years, a technology called CRISPR-Cas9 has revolutionized scientists’ ability to make precise changes in the DNA of a wide range of organisms. By being cheap, relatively easy to use, and effective in almost every species tested, this genome editing method is putting another technology, called gene drive, within reach for many organisms. Because gene drive shifts biases inheritance to favor certain versions of genes, a genetic alteration introduced into a few members of a population spreads rapidly throughout the entire population. If that alteration inhibits reproduction or survival in some way, gene drive can drive that population extinct in theory. In other uses, a desired trait could be driven through a population.
Last year, Harvard University biologists proposed CRISPR-Cas9 gene drive systems be used in conservation to get rid of invasive species or to improve the genetic makeup of endangered ones. A few scientists immediately called for increased regulation of this technology because, once released, a gene drive could be hard to stop or reverse. And in July, geneticists showed that one gene drive system was almost 100% effective in spreading a mutated pigmentation gene through a population of lab fruit flies, fueling fears about the power of gene drive.