The research, published today in the journal Cell, challenges a common perception that gender is determined purely by the X-chromosomes and Y-chromosomes. The gene that was switched off, known as FOXL2, lies on a non-sex chromosome that is shared by males and females.
“We take it for granted that we maintain the sex we are born with, including whether we have testes or ovaries. But this work shows that the activity of a single gene, FOXL2, is all that prevents adult ovary cells turning into cells found in testes,” said Robin Lovell-Badge, from the National Institute for Medical Research, a co-author of the paper.
The practical use of this is that it might improve sex change therapy in that genetically-altered testicles or ovaries would begin to produce the intended hormones on their own.