Female mice can be turned lesbian by deleting a single gene, South Korean researchers have found.

The study, published in the BMC Genetics journal, found that when the FucM gene, which influences oestrogen levels in the brain, is disabled, female mice lose interest in males and try to mate with other females.

Researchers believe that when the gene is deleted, the mice are exposed to extra oestrogen. In mice, this masculinises the brain, although the effect does not occur in humans.

Professor Chankyu Park of the Korea Advanced Institute of Science and Technology in Daejon, who led the research, told the Daily Telegraph: “The mutant female mouse underwent a slightly altered developmental programme in the brain to resemble the male brain in terms of sexual preference.”

He added that he hoped to investigate further to see what effect the enzyme produced by the gene has on human sexual orientation, although he admitted it could be difficult to find volunteers.