Scientists at the University of California, Davis, have successfully produced a bull calf, named Cosmo, which was genome-edited as an embryo so he’ll produce more male offspring. The research was presented at an 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.
“We anticipate Cosmo’s offspring that inherit this SRY gene will grow and look like males, regardless of whether they inherit a Y chromosome,” said Alison Van Eenennaam, animal geneticist with the UC Davis Department of Animal Science.
Van Eenennaam says part of the motivation to produce more male cattle is that male cattle are about 15% more efficient at converting feed into weight gain. They are more fuel-efficient than females. Continue reading