That Project Rebirth, the program that created Captain America was actually secretly part of Weapon Plus, the organization that captured and bonded Adamantium to Wolverine; the X in Weapon X actually being 10, with Deadpool being Weapon XI and characters like Fantomex being Weapon XIII.
But wait, there's more!
Weapon Plus was actually started by a man named John Sublime, and John Sublime was possessed by a sentient bacteria colony that came to earth millions of years ago to enter a symbiotic relationship with life on Earth that eventually came to hate mutants because they were the only species that were immune to it.
It's stupid, but it's comic book stupid, which makes it great!
And there's more!
Humanity's initial spurts of irrational hatred for mutants is largely Sublime's fault through subconscious influence to get humans to come up with ways of driving mutants to extinction!
But wait, there's more, said sentient bacteria has a sister bacteria named Arkea that can possess technology.
but wrapping back to the Project Rebirth/Weapon Plus thing, there's very few corners of Marvel not touched by them. The Infinity Formula that Nick Fury used was originally derived from them before Hickman's retcon of it being created by Leonardo Di Vici or some shit, we have characters like Sabretooth, Team X,and so on. Emma Frost has five daughters rapidly aged into late teenagedom thanks to their experiments, Mr. Sinister infiltrated them back in the 50's, and so on.
Weapon Plus runs deep in Marvel.