User blog comment:The Many-Angled One/I Know What Cyclops Did Last Summer/@comment-2204174-20151228181503/@comment-5448995-20151229085057

But mutants have been exposed to huge amounts of the mist already and the mist has been going around for a while now.

Yeah like I said they were Inhumans modified by Apocalypse but humans first, still and I've only read the official guide like you if he changed them by giving them the X-Gene that would make them mutants(I think) but I don't know if that is the case.