Scientists at the University of California, Davis, have successfully produced a bull calf, named Cosmo, who was genome-edited as an embryo so that he’ll produce more male offspring. The research was presented at the American Society of Animal Science meeting.
Using the genome-editing technology CRISPR, researchers can make targeted cuts to the genome or insert useful genes, which is called a gene knock-in. In this case, scientists successfully inserted or knocked-in the cattle SRY gene, the gene that is responsible for initiating male development, into a bovine embryo. It’s the first demonstration of a targeted gene knock-in for large sequences of DNA via embryo-mediated genome editing in cattle.
The scientists anticipate Cosmo’s offspring that inherit this SRY gene will grow and look like males, regardless of whether they inherit a Y chromosome.
The motivation to produce more male cattle is that male cattle are about 15 percent more efficient at converting feed into weight gain. They are more fuel-efficient than females. Additionally, they tend to be processed at a heavier weight.
It could also be a win for the environment, with fewer cattle needed to produce the same amount of beef.
As the Food and Drug Administration regulates gene-editing of animals as if they were drugs, Cosmo and his offspring will not enter the food supply.
News Source: University of California, Davis
