Interesting - what sorts of congenital defects? I've been around a handful of isolated communities like that, and have definitely been to places where the peop

Interesting - what sorts of congenital defects? I've been around a handful of isolated communities like that, and have definitely been to places where the people looked both very much alike and very "atypical" compared to the population at large, but I'm not sure I would describe what I've seen as "defects". Rather, my assumption is that in a smaller population like that is that some characteristics are exaggerated while others are suppressed. As an example from my own family, my grandfather had nearly white hair and ears that were somewhat larger than normal. He was called "Cotton" when he was in the military (WW2/Korea) and later in life when he worked as a mechanic. The area he grew up is about two hours from me, and is a town of about 100 people. It's striking how many of them have big ears and very light hair, especially the older generation. I wouldn't consider a high prevalence of light hair and big ears to be "defects", though. Is that the sort of thing you're talking about, or was it something more substantial?