Is gender moulded by your environment? How so?

For a long while, I have been rather neutral in the heated debate between empiricists and nativists. However, after being exposed to the documentary on the curious case of David Reimer, as well as doing some additional research by my own accord, I have arrived to a conclusion on the debate. After a long period of thought, I have concluded that I agree more with the nativists on the topic, and stand by my own claim that gender, while able to be modified by the environment you grow up in, is still inevitable determined by genetics. This stems from two major points: the first being David Reimer himself, the second being the study conducted by Dr. Milton Diamond. To begin with, let’s talk about David Raimer; a man who was born female but, due to a circumcision gone wrong, became a female through extensive hormonal therapy and gender reassignment surgery. The first quirk from the traditional man-chooses-to-become-female formula we’ve become accustomed to is the fact that David didn’t choose to become female, rather was assigned that gender. Later in his life, he confessed to being bullied due to a choice his mother made for him in his childhood, and eventually decided to return to the male sex. Tragically his life ended in suicide, aged just 38. From this, we can detract two points to support my claim. The first is that he still identified as a male, despite the hormonal therapy and surgery he underwent as a youth. This means that, despite what can be done after birth (aka nurture), genetics win out in the long run (aka nature). The second point is a more complex one, and is a more of a moral dilemma than a scientific one. It being: what are the psychological consequences of gender changing surgery? David suffered from depression and gender dysphoria (though from the gender he had been assigned, rather than the one he had been born with). Could these be a consequence of his difficult childhood, or perhaps a byproduct of his extensive gender-change process. The second point of article I mentioned was the study conducted by Dr. Milton Diamond on how hormones affect gender. While I won’t bore you with the tedium of the entire study, the basis of it was injecting female rat embryos with testosterone (a male hormone), then seeing how the rats developed. Strangely enough, the female rats behave markedly by males, at one point even attempting to mate, despite their lack of organs to do so. To conclude, it is my firm belief that nature wins over nurture in the determination of gender.