BobTheSqueakyWeasel Posted:

Or they’re just trying to make the best of what’s already a pretty ****ty situation by maximizing the overall difference, despite the overwhelming similarity between the genetic code of any two humans. Having a child with your sibling is much more likely to result in birth defects than having a child with somebody that’s separated from you by three or four generations of reproduction. If every child that pops out of the bunker is immediately related to every other child, the problem of inbreeding becomes much, much worse.

But your idea’s good, too.

It mostly just magnifies and enhances the possibility for dangerous, recessive genes to come out in the phenotype. It’s not really that detrimental, and a 9-person genetic bottleneck is really pretty much just as bad as incest. After the first 2-3 generations they’re all going to be completely inter-related anyway, so it’s kind of a moot point.