Today we know very well that being trans isn't a sexually fueled mental illness, however we still need to understand how the nature of wanting to be the other sex encompasses elements of sexual energy.
Guest post by Joanna Santos
Since all of the trans people I know trace their gender feelings to before puberty, it would be far too simplistic to try and reduce feelings of gender incongruence to sexual dysfunction.
Blanchard reducing gender identity to misdirected sexuality
However the now infamous Ray Blanchard did his best to do so and by the late 1980's was simply dismissing testaments of early childhood gender dysphoria by his patients as lying (hardly a scientific method) so they could fit a narrative aimed at transition.
He eventually concocted a theory that attributed that desire as either a misdirected sex drive or wanting to attract heterosexual men as partners (in the case of patients attracted to men). He called the made up disease that supposedly drove those of his patients who were attracted to women "autogynephilia."
At this point let us simply state that some forms of gender variance exist primarily for the achieving of sexual arousal, which only adds confusion to the mix.