“Epigenetically programming gender identity
by Leslie K. Ferrarelli
The presence or absence of a Y chromosome dictates our biological gender. However, the brain is wired to be female unless exposed to testicular steroids (such as androgen and its metabolite estradiol) during a sensitive period shortly before and after birth. The most sexually dimorphic region in the brain is the preoptic area (POA)…steroid-induced gender identity in the POA is mediated by an epigenetic mechanism, specifically DNA methylation…methylation were lower in the POA of male newborn rats than in those of female newborn rats….The findings further define how neurological gender identity is determined.