I read that when you are breeding animals (i'd say its true for humans too) that its ok to breed a brother and sister, just not too many times down the generation line. If it happens too many times there is more chance of the two siblings to have a very similar dna structure.
So is you have kids with your brother, as long as your parents arent incest then there is a small chance your kids will have deformities.
So is you have kids with your brother, as long as your parents arent incest then there is a small chance your kids will have deformities.