A viable herd of genetically uniform cattle - Deleterious alleles seem to have been purged in a feral strain of inbred cows

Abstract

Inbreeding, which can lead to the loss of genetic variation or the accumulation of deleterious alleles, has been shown to reduce fitness in wild (1), zoo, laboratory (2) and farmed (3) animals. But it has been proposed that when combined with selection, inbreeding may purge deleterious alleles (4). Here we provide support for this hypothesis in a study of the Chillingham cattle, which shows that this viable herd is almost genetically uniform. The homozygosity of this herd far exceeds that of other cattle (5) and that found in wild populations of other mammalian species (6,7).