Why does inbreeding result in a higher chance of genetic defects?

Question

Why does inbreeding result in a higher chance of genetic defects?

In: Biology

Answer 1

If the parents are not related they might carry some recessive genes that could result in genetic diseases but it’s rather unlikely that both have the same so the offspring has only a minute chance of getting 2 ‘defective’ alleles of the one gene. When the parents are closely related on the other hand it is rather likely that both carry the same recessive genes which means there is a pretty high likelihood of the offspring getting 2 defective alleles that will express the genetic disease.