English word mutagen comes from English mutate, English -gen (A producer of something, e.g. hydrogen.)

Detailed word origin of mutagen

Dictionary entry	Language	Definition
mutate	English (eng)	(intransitive) To undergo mutation.. (transitive) To cause mutation.
-gen	English (eng)	A producer of something, e.g. hydrogen.
mutagen	English (eng)	Any agent or substance that can cause genetic mutation.

Words with the same origin as mutagen