Board Thread:Warhammer 40k General Discussion/@comment-7699236-20150618150629/@comment-18016240-20151211064401

All of the heresy!

...Actually, you know how in the Fallout universe there's Super Mutants who were once women, but the FEV made them look male due to some of it's effects? That might be how the Astartes' gene seed works too.