The speed with which Law's eyes flick up and turn keen betrays his interest in the idea. There's a touch of dread in there, too. "Maybe," he answers, and then clarifies. "It depends on how. If their lineage factor has been altered, I don't know that anything I can do would fix it." He's aware that it's called something different in some worlds, what was it? "I mean. Genetics. The basic code at the cellular level."

Really, if he could alter DNA, he'd be able to remove Devil Fruit from their users. That shouldn't be a thing, it would be dangerous to have that power.