Pyrrhos: his son and daughters married?

[Sumskilz]

No, it doesn’t produce retarded offspring, but it does increase the likelihood of them receiving genetic illnesses caused by recessive traits. Most genetic illnesses are caused by a mutation at a specific allele. For example, if a random mutation occurs at a specific allele in a royal bloodline, it isn’t really an issue as long as each individual has at least one good copy of the gene, but inbreeding increases the likelihood of having two copies of the bad gene and thusly the disease.