A ‘gene drive’ makes its debut in mammals

Abstract

Researchers for the first time have engineered a "gene drive" in lab mice to speed the inheritance of a gene. Gene drives, which have worked in insect experiments done in laboratories, have received intense scrutiny because some researchers hope to use them in the wild to eliminate disease-causing or crop-destroying pests, but this experiment sidestepped the controversy by focusing on creating a simpler way to genetically alter traits in lab mice. The team from the University of California, San Diego, used the genome editor CRISPR to put a gene in the mice that modifies their coat colors. But they also engineered these same mice to pass on the genes that create CRISPR itself so that progeny edit their own genomes to carry the coat color–modifying gene. When they mated an engineered mouse to a normal one, it should have created a pup with the coat color–modifying gene in one of two chromosomes. But because the pup also inherited CRISPR, it altered the unmodified chromosome passed down from the normal parent so that it, too, had the gene. The experiment, in bioRxiv—a preprint server that is not peer reviewed—only worked when the researcher controlled the timing of the CRISPR reaction so that it happened during meiosis—and it didn't work in males. The researchers stressed that the use of gene drives in mammals to control pests is still a long way from becoming a reality.