should there be a reason on why some mutants can talk?

[Luckyday]

I know mutagen is unpredictable but....would it ruin the mythos of TMNT if they came up reason like say their ancestor was a mutant during the dinosaur era but was beastly non self aware (like monsters we seen in the show) and had somehow sired descendants but those descendants regress back into normal animals but if those descendants get touch by a mutagen then those will get more positive results like gaining a higher intelligence and have less negative results like looking deformed, sick or case of the crazies.