Found this today online. Sorry if it's a repost.
Transsexual differences caught on brain scan
12:16 26 January 2011 by Jessica Hamzelou
Differences in the brain's white matter that clash with a person's genetic sex may hold the key to identifying transsexual people before puberty. Doctors could use this information to make a case for delaying puberty to improve the success of a sex change later.
Medics are keen to find concrete physical evidence to help those children who feel they are trapped in the body of the opposite sex. One key brain region involved is the BSTc, an area of grey matter. But the region is too small to scan in a living person so differences have only been picked up at post-mortem.
Antonio Guillamon's team at the National University of Distance Education in Madrid, Spain, think they have found a better way to spot a transsexual brain. In a study due to be published next month, the team ran MRI scans on the brains of 18 female-to-male transsexual people who'd had no treatment and compared them with those of 24 males and 19 females.
http://www.newscientist.com/article/dn20032-transsexual-differences-caught-on-brain-scan.html#.UstaxfRDsRA----------
Basically, they scanned Transsexual brains on a MRI, and found that FTM brains looked just like gmale brains, and a different study found that MTF brains where kinda in the middle. Not to masculine, but not to feminine ether.
In a third test, they say that 38% of 121 Transsexuals knew they where Gender variant by the age of 5.
