biology and gender
The idea that that homosexuality is inherent (for example the idea of a gay gene) has generally been appealing to the gay community. Obviously there is the danger that a biological approach can lead to seeing homosexuality as a defect that can be fixed, but it should lead to better policy to see homosexuals as an inevitable part of the community not as people who have chosen a bizarre lifestyle. The greater danger is that our biology will take away our choices--if you have a particular gene must you be gay, or if you don't you can't be? I do not think people would be happier if they could find out with a blood test.
And yet there is something so seductive about having biological evidence for who I am. I finally found out the results of the rest of my lab tests, and my testosterone was 67 in a reference (normal) range from 15 to 76. The doctor had originally speculated it was high and suggested medication, and my reaction was very clear that I like being masculine. Clearly it is more important to my identity than I had realized, though I am very happy with the life I have chosen.