""A homosexual gene would be doomed to extinction unless it was recessive and conferred some survival or reproductive benefit on heterosexual carriers.""

NONSENSE!   There are any number of genes in the human genome which have NO discernible survival potential, yet are obviously NOT doomed to extinction because of that.

Blonde
Brunette
Redhead
Pale skin
Dark skin
Albino
Blue Eyes
Brown Eyes
Hazel Eyes
Tall
Short
Fat
Thin

and on, and on, and on.......................................

Learn a little about heredity before making foolish statements.

Don T.