Board Thread:False Info and Speculative Discussion/@comment-4772791-20160123002637/@comment-26879545-20160213172209

Neilandio wrote: Identical twins have the same DNA, so I don't think their merge makes them genetic chimeras. That's actually only true right after the egg splits. As embryos, identical twins share the same DNA, yes. However, when those cells divide there's a chance that there'll be a mutation in the DNA. As such, they'll have nearly identical DNA with the exceptions of the mutations, which would be unique to each twin.

As for whether Ethan and Aiden's merge power would make them chimeras, I highly doubt that they'd become genetic chimeras from merging. Unless they somehow swap bone marrow or any organs when merging/de-merging, their DNA sets would still be their own after they split off from their combined "Aithan" (just gonna give their merged form a name for the sake of this post) form.