Would this experiment actually work? Suppose you were to take an infant that grows up and becomes a trannie by the age of 30. Doesn't matter if it's female-to-male or male-to-female.
Now, go back in time and clone that infant one hundred times. You now have 100 clones and 1 original. The original stays with it's own family and the 100 clones are scattered all throughout the world to adoptive parents. Clearly, you'd want to match race and language in order to avoid those variables from affecting the experiment. Now, you allow those 100 clones to grow up with no interference to see if any of them become trannies by the age of 30.

How many of the 100 clones would have to become trannies in order for it to be scientifically determined that trannie-ism is biologically based?