The question that came to my mind about homosexual incest is; does homosexual incest cause more or less problems than hetero-incest?
Probably more since people still aren't very accepting of gay people and that on top of incest would be even worse.
It's all about dominant and reccesive genes. If two resecives pair up they are displayed. It is more likely for them to pair up if both people ahve them. This is more likely when they are related. If the recessive genes are dangerous, tht is where problems occur.