There are no bad genes, there is no right or wrong when it comes to DNA.
As far as I remember, bats are the animals with the highest rate of homosexuality and I'm sure humans didn't help with that.
Gays are productive members of society. Give them the right to marry and adopt. You'll see less orphans that, what ya know, appeared because of some dumbfuck straight folks that can't keep it in their pants.
And the productive part? They can do a job any straight person does and heck, you'll never even know their sexual orientation. Because it doesn't matter.
Straight people really care about marriage too. I mean, they marry someone they met in a bar 5 minutes ago. Or they've been married 6 times and hell, are gonna get married again someday. I'm sure some gays would be exactly like this if they were allowed to marry, but there's also gay couples that have been together for years and would like to just make it official, but homophobes are stopping them for no reason whatsoever.
Long story short, I see nothing wrong with gay people.
Believe you me, this took longer to write than I should admit. I need to use my brain more often, I'm becoming too stupid.