if procreating with close relatives causes dangerous mutations and increased risks of disease, how did isolated groups of humans deal with it?

Question

if procreating with close relatives causes dangerous mutations and increased risks of disease, how did isolated groups of humans deal with it?

In: 562

Answer 1

Inbreeding does not cause dangerous mutations. Inbreeding has no effect on mutation rate. Instead, inbreeding increases the likelihood of someone inheriting two identical copies of a gene (homozygosity). A lot of dangerous conditions are recessive, which means you don’t get the disorder unless you have two copies of the “broken” version of the gene. If instead you have one “broken” copy and one functional one, you’re fine. Inbreeding makes inheriting two “broken” genes more common.