Doesn't gay marriage guarantee the extinction of homosexuality?

Bear with me.
For starters this is a scientific question, so it is in General and if you give me shit, I will flag the answer.
Furthermore, to put it in context, and to avoid your frequent misrepresentation of me, I will, once again, as I seem to have to do occasionally, articulate my views on certain social issues
1 I am opposed to capital punishment
2 If a woman wants to hire a doctor to perform an abortion, the State has no interest in stopping it
3 Having spent about half my life in the pursuit of it, US foreign policy is a little trigger happy.
4 Corporations are not individuals and should not be governed by the same rules as individual citizens regarding political contributions (Full disclosure, neither should unions)
5 FINALLY Homosexual couples should not be denied legal recognition of their commitment to one another

But, if we grant the question that being homosexual is NOT a rational choice but in fact a genetic imperative, then the homosexual gene can only be transmitted by procreation where at least one of the partners is homosexual.
But homosexuals cannot transmit the homosexual gene, because they can not procreate.
So if the Political State grants to homosexuals the legal legitimacy of their commitment, do they not also doom the the genetic line of homosexuality.
And if the answer is, that homosexuals will indoctrinate their adopted children to the lifestyle, doesn’t that contradict their genetic argument?
You say.