The numbers of gay and lesbian people are a lot at least where I live. I seem to run into them a lot.
They are from all racial backgrounds, My observations not scientific, have shown me that something is lacking. Maturuity or lack of, strikes me as a possible reason. People that have had hurtful relationships sometimes head in that direction because they don't want to be hurt again.
Men that a couple of generations ago would probably marry, are openly gay I think because of the womens movement.
My statements are only what I have observed.
There has also been much talk recently about the possible connection between abuse (physical, verbal or sexual) and homosexuality. I first heard this from a person deeply involved in matters of faith a several years ago. It now seems to be being discussed more and more. I wonder.