When reading about somebody objecting to incest in another thread something occurred to me, since many people do want to allow incest but only between consenting adults, and that they should not be allowed to breed because the children have a chance of being somehow deformed, in mind or physically. While there is evidence to the contrary (many monarch-families have been in-breeding for a long time without many problems for example), if we assume that this is true then should we allow people that are challenged to breed, due to the high risk of deformed children, according to the same logic?