Researchers at China’s Northwest Agriculture and Forestry University tailored a CRISPR/Cas 9 technique to give cloned dairy cows a leg up against the bacteria behind bovine tuberculosis (Mycobacterium bovis), a threat to cows in many parts of the world. Last year, another group used TALENs, an older gene-editing technology, to create two cows without horns, but this is the first time scientists have reported using CRISPR to insert a gene in cattle.
The team cut and pasted a bovine gene that codes for NRAMP1, a protein linked to resistance against TB and other bacterial infections, into the genomes of fetal dairy cow cells. Through cloning, mother cows gave birth to 20 calves with the NRAMP1 gene. Of the 11 calves that survived past three months, six were tested for TB resistance and showed heightened TB-fighting abilities, the team reports February 1 in Genome Biology.