Puzzle no more Steve,the long, weary and unfulfilled search for a genetic link, is simply an attempt to validate homosexual behaviour, to prove that homosexuals are indeed, a different third sex of humanity.

Without the genetic link, which given the progress made in genetics over the last couple of decades, should be as obvious as the nose on your face, homosexuality would be just another minority sexual behaviour, like incest.

To validate the practice a genetic link is required and in all probability will be manufactured "to measure"

Unfortunately this will open a new can of worms as other less well supported groups queue up to be validated by science.
The future for society looks bleak.