Transgender identity might be genetically determined, at least partially, results from the world's largest study of transwomen reveal.

Fran took part in the study because she believed it might help people. Credit:Luis Enrique Ascui

The team behind the study say they have found evidence of a genetic link underpinning gender dysphoria: when your sense of being male or female differs from the gender you were assigned at birth.

The study, published in the Journal of Clinical Endocrinology and Metabolism, is the result of a painstaking 15-year project to build the world’s largest DNA database of transwomen - people male at birth who have transitioned to female. Three hundred and eighty transwomen signed up, and the findings were compared to a control group of 344 males.

Using the data, a team from the Hudson Institute of Medical Research at Monash University studied 12 genes related to sex hormone signalling.