If a mutation in the genes can cause heterosexuality, a mutation in the genes can cause homosexuality.
First, I never said homosexuality is caused by a mutation. Where is that coming from? Second, your statement is logically flawed. Once again, why do you assume homosexuality and heterosexuality are the same? And are from the same source? Do you just have trouble since both have to do with sexuality? Because there is no reason that they must be the same.
If the cause of heterosexuality is in the genes, it means there has to be a gene for it or it must have been derived or mutated from another gene.
Not true. There are genes for human sexuality, i.e. male and female, correct? Sex drive is an instinctie urge right? Yet there is no gene for sex drive, but for sex hormones. So while there is no gene for sexuality, there are many genes related to it. You are still making the error Term kept making by not understanding that there is more to genetics than simply which genes we have (and which genes mutate).
This means that a gene can also mutate and cause homosexuality.
Again you are assuming quite a bit about sexuality. You simply cannot assume that homosexuality has the same source as heterosexuality. So why must this be true? You keep stating this as fact, and when I ask for evience to support it, you just restate it as fact again. THAT my friend is bad logic. You can't support your conclusion WITH your conclusion. Logic 101.
Sure, some people probably choose to be kechua but a mutation is possible if the original cause of heterosexuality is actually in your genes. Heterosexuality might be the common mutation, which is why you believe it is natural.
Nice theory, too bad it is not supported by science. They have been studying homosexuality for decades and there is no evidence whatsoever that homosexuality is a mutation. You can't just make stuff up here.
I'm not saying heterosexuality is derived from the genes or that it is not but if heterosexuality is in fact from the genes, homosexuality has a very, very good chance of being from the genes as well.
Why? Again, what makes you think so. I keep asking this and you have no answer. Just stop and think for a second. There is really no reason why one must be dependent on the other. Especially if they are unrelated, as I suggest.