Transsexuality, also termed 'Gender Dysphoria' is now reaching the point of being reasonably well understood, though many myths and general foolishness about the subject still abound. This document concerns the classic definition of transsexuality, as defined by Benjamin, Money, Green, and so forth. Intersexuality and transgenderism will not be addressed other than obliquely.
IN A NUTSHELL: This is about standard, classical transsexuality.
Gender Dysphoria, literally a misery with regard to gender, is the condition of being in a state of conflict between gender and physical sex.
A transsexual is a person in which the sex-related structures of the brain that define gender identity are exactly opposite the physical sex organs of the body.
Put even more simply, a transsexual is a mind that is literally, physically, trapped in a body of the opposite sex.
IN A NUTSHELL: Transsexuality means having the wrong body for the gender one really is.
Gender and Sex are very separate things, though the terms are often considered interchangeable by the less aware. Sex is physical form and function while Gender is a component of identity. There can be considered to be some legitimate overlap in that the brain is structured in many sex-differentiated ways, and the brain is the seat of identity. However, with regard to the dilemma of the transsexual, the difference between sex and gender are at the very core of the issue.
A transsexual person, born to all appearance within a given physical sex, is aware of being of a gender opposite to that physical sex. This conflict, between gender identity and physical sex, is almost always manifest from earliest awareness, and is the cause of enormous suffering. It is common for transsexuals to be aware of their condition at preschool ages.
This agony can and does lead to self destruction unless treated. The incredible difficulties that surround achieving treatment are themselves often agonizing, the sum total of which can play havoc with the lives of the gender dysphoric. Indeed, it is apparent that some fifty percent of transsexuals die by age 30, usually by their own hand.
The standard treatment for a diagnosis of transsexuality is to reassign the transsexual to a physical sex congruent with their gender identity, a process involving the administration of appropriate hormones and surgery. The success of this treatment is exceedingly high, and many transsexuals go on to live successful lives.