Had to finally chime in. As a developmental biologist and teacher of human sexuality, I have found the conversations filled with "great thoughts" and pure idiocy.
   There has never been a "gay" gene found; to think that a single set of genes could regulated such complex behavior is beyond the pall. There is little question, however, the multiple genes are involved along with epigenetic factors, chemicals such as hormones that regulate brain development. Many such examples exist.
    So, is "gayness" a choice -- no! Is our sexual behavior a complex of early developmental factors -- extremely likely. Please -- no more choice dogma. No reputable social psychologist would argue for choice.
   Interesting thread!