Mutations that knock out the function of some proteins don’t lead to health problems
Many genes may be dispensable.
Each of 3,222 British people with Pakistani heritage carries, on average, mutations in 140 genes that stop those genes from working, researchers report online March 3 in Science. Examination of those people’s exomes, the small portion of the genome that encodes proteins, revealed that among a subset of 821 participants, a total of 781 genes were rendered obsolete by “loss-of-function” mutations. Those genes include 422 that scientists didn’t know people could live without and still be healthy.
Previous studies had indicated that some genes are commonly missing in healthy people. The new study suggests that even rare mutations that disable both copies of a gene, which scientists thought would be associated with diseases, aren’t necessarily a problem.