American Horror story has a sociopath. His Mother on the show said something to the effect of "He is just like his Father., that is what happens when cousins marry. " They seem to have at least one full fledged sociopath character per season. And a lot of Narcissists.
A lot of wealthy families have inbreeding.
Now, that is true. That is how certain "genes" are passed on. Look at British aristocracy for example, The "Blue Bloods." There is a reason they had a family of rulers with certain leadership or sociopathic traits.
The Bernie Madoff's of the world don't mingle with the rest of us. I have read that his son was in on his Ponzi scheme.