It is preposterous to liken being black to being a homosexual. being black is a physical characteristic encoded in the gene. the skin color is directly influenced by the genetic make-up of the individual and that pigmentation is an adaptation. homosexuality is not something encoded in the gene per se. the human genome codes for individuals with the ability to procreate sexually. so they are formed with the physical adaptations for that. hormones and the reproductive system lead the individual to develop a reproductive behavior which involves sexual attraction to a complementary sex. And here lies the critical step because at this stage it means the development of a reproductive behavior is not directly and entirely controlled by the genes but also largely influenced by brain functions and processes, which in turn is largely influenced by the environment. As Richard Dawkins explained in his classic work ,The Selfish Gene, the brain evolved to make quick decisions and adapt to sudden changes in the environment which will be otherwise to fast for the genes themselves to adapt to directly. And as it is natural with such rapidly changing systems and processes errors or unintended and expected outcomes become more probable, so success to produce individuals with coherent reproductive behavior in accord with the anatomy becomes less restrictive and so individuals are spawned whose reproductive behavior is inconsistent with their phenotype.
It is a scientific fact ( though not necessarily a political one) that sexual behavior not coherent with the human anatomy is a dysfunction because the genes do not code for an anatomy that fits a homosexual behavior. if this dysfunction happened  at the level of the genes it is mostly called a mutation or a genetic diseases or genetic defect. Such as albinism. Most mutations are disadvantageous. In fact disadvantageous mutations tend to limit the ability of an individual to pass on its faulty gene so that it  does not enter the gene pool and lead to extinction of the species.  I strongly believe homosexuality in humans could be a result of a defective gene but a lesser influence than the psychological and environmental component. And that the genetic influence may vary in strength from one individual to the other. Thus my guess and observation is homosexuals should not be allowed to donate sperm or eggs for fertilization because that very practice could be the very doom of humanity especially those who are gender-confused, such as transsexuals, cross dressers, effeminate men etc because this particular group seem to exhibit a form of reproductive behavior dysfunction that may be to a greater extend influenced by the gene component .

In conclusion, all our hate and love are just aspects of the survival of genes. Love must not be erotic to be love. And not all hate is hate. The ability to be disgusted by something is what keeps one from committing murder, for instance, or having sex with close relatives. Being disgusted by the thought of incest is an adaptation which is part genetic and part (mostly) psychological, which we know is missing or deminished in some people. Being disgusted by homosexuality is all but a natural and normal adaptation.    I personally see homosexuals in the same light I see all sexual defiance: dysfunctional reproductive behaviors.