It is said Chimera Ants made from humans keep some of the characteristics from their human life. Do we have any hint about Meruem's human identity ?
I believe that because his birth was fueled by so many humans it is impossible to say that he was born from any particular one despite clearly having human DNA and features. This is similar to the way Youipi was born from a magical beast. The King, as he explains in his fight with Netero is instead the culmination of his entire species' evolution.
I always figured it was that one dude who founded the NGL as it showed that he had a caring side as well as a violent uncontrollable rage that wanted to lash out at humanity I just thought they wouldn't introduce a whole character like that and give a backstory just to show the NGL's founding it just made sense to me for him to be Meruem in his human life