I'm guessing, though it doesn't mention anything here, that in most of these cases, it's more than just genetics at play and we're looking at the result of multiple generation inbreeding???
Wierd stuff for sure.
"One hour from now, another species of life form will disappear off the face of the planet, forever, and the rate is accelerating.." - excerpt from Megadeth's Countdown to Extinction
And it's up to us to stop it - Gorelith