Talk:Coup de Grâce/@comment-66.68.72.229-20150206050554/@comment-25900245-20150208030737

"[...] all of the Ark residents are the same blood type, Type O (the universal donor blood type). This is fairly easy for them to engineer genetically [...]" (Writers blog)

I don't think there has ever been a statement that the Arkers ability to process radiation is as a result of genetic engineering. Clarke knew about the genetic engineering but didn't appear to know why her people would be able to process radiation, although she does work it out pretty quickly... (S02E01)