Here's something transgenderists and those who love them already knew, but I suppose an official medical study will help others to understand.
STUDY CHALLENGES GENDER IDENTITY
from The Los Angeles Times (Registration Required)
Male babies surgically turned into girls at birth because of a rare birth defect frequently continue to feel like boys and may eventually switch their gender back to male, even with no knowledge of their history, according to a new study.
The finding, reported in the current issue of the New England Journal of Medicine, suggests there is an intrinsic, biologically determined feeling of sexual identity that is hard to override through rearing, experts said.
The study also suggests that surgeons should reexamine the practice of altering the gender of babies born with this condition.