Emily's Cat
Rarely prone to hissy-fits
The nature vs. nurture debate is a longstanding topic in psychology, so, yes. There have been studies for example, that have shown that adopted children are more like their biological parents than their adopted parents.
As far as transgender (I know, it's wikipedia):
https://en.wikipedia.org/wiki/Causes_of_transsexuality#Genetics
To me, this suggests that there are both genetic and environmental factors in someone being transgender.
I question their hypothesis of incomplete masculinization during fetal development... given that the majority of their transgender subjects were already undergoing hormone therapy. How did they control for the effect of intentional testosterone suppression and the artificial application of estrogen on the receptor in question?
That's a flaw I've seen repeated over and over in research on the brains of transgender individuals, seeking to find a neurological cause. They look at scans for adult transgender patients who are already taking cross-sex hormones.
There's a similar flaw inherent in the studies of male versus female brains, looking for 'innate' differences. They look at the brains of adults... who have been subjected to social conditioning that is sex-divergent. They don't control for neural plasticity.
I'll have to see if I can find it... there was a study that looked at the brains of newborns, and saw no innate differences aside from size, which was a direct affect of males having larger heads on average. I believe there is one very specific part of the brain that shows strong sex-differentiation from infancy - it's the part of the brain that is responsible for sexual attraction and sexualized behavior. It supports arguments that homosexuality is an innate feature... but it has nothing at all to say about gender identity.
