Also, would it be possible that the mixed race children be able to breathe both oxygen and nitrogen? Like, their bodies would start off with oxygen and if the oxygen was cut off somehow, they would automatically switch to breathing nitrogen? Or would this result in some sort of explosive reaction I'm not aware of? (Science was never my strong subject.)
Used searches like, "What if we breathed nitrogen?" which came up with links describing how we would die if all we had in the air around us was nitrogen since we breathe oxygen. Not at all helpful, in other words.