Nuclear accidents mutating everyday people were common in pre-Marvel tales...
...plotted or written by Stan Lee for Atlas Comics...except they didn't result in costumed superheroes...or costumed supervillains!
If this never-reprinted story by plotter Stan Lee, scripter Larry Lieber, penciler Matt Baker and inker Vince Colletta, from Atlas' World of Fantasy #17 (1959) had appeared after the intro of the Fantastic Four in 1961, I don't doubt Frederic Kane would've become an ongoing super-villain and scientist brother Phillip would've become his nemesis, probably working with S.H.I.E.L.D. and/or Professor X to stop him!
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