Study In Transsexuals: Significant Genetic Link To Gender Identity

In the largest ever genetic study of male to female transsexuals Australian researchers have found a significant genetic link between gender identity and a gene involved in testosterone action.  From an early age people develop an inner sense of being male or female – their gender identity. Transsexuals however, identify with a physical sex opposite to their perceived biological sex.  DNA samples were collected from 112 male to female transsexuals and researchers compared genetic differences with non transsexuals.

http://www.sciencedaily.com/releases/2008/10/081030111005.htm