I think I understand your concerns Janet. And, believe me I do not take them lightly. However, (first my disclaimer: I am not a doctor, geneticist, or a psychiatrist, these are only my unprofessional assumptions and opinions) I think this may open the door to a more verifiable genetic component to why we develop the way we do. This particular case in the way I read it may really give more light to how women who are born with AIS can be understood and maybe helped, than it does to us as transexuals (excepting maybe FTM's).
The issue of what it actually means for "us" can be troubling if the actual "Trans" gene is found. I think everyone can understand the implications of the "cure" that could be developed in such a situation. I actually can see benefit and problems from such a determination if they ever do actually find that gene. After all, once you've been born with this condition, and are a living breathing person, it's not bloody likely that someone short of a bigoted supremacist type (much as they do now), would be able to argue that we need to be cured by altering our gene's. Rather, as shown in the article, the real intent is to get the body caught up with where the mind is at. And, isn't that what we all know within ourselves, is what needs to happen?
Yet if by this study it is shown that in not only FTM's but, also MTF's can develop the desired sexual characteristics, it sounds like a lot shorter and much, much safer, not to mention less expensive potential treatment than what we currently are offered.
As for the DSM I think it is high time we were out of that gatekeeper handbook and allowed to move into the realm of real medicine and treatments to match! But, that is just my opinion. I don't pretend to know all of the politics of this particular argument but I am willing to listen and learn!
In any case it is fascinating at the progress and development of these studies as are showing up these days.
Dawn