A comutagen is a substance that is not a

mutagen In genetics, a mutagen is a physical or chemical agent that permanently changes nucleic acid, genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can ca ...

by itself, but in the presence of a mutagen, enhances mutagenic activity. There are at least two manners by which this may occur; the comutagen may strengthen the mutagenic activity of mutagenic chemicals, or it can create a mutagenic response from nonmutagens. Chemicals such as harmane and

norharmane β-Carboline (9''H''- pyrido ,4-''b'' ndole) represents the basic chemical structure for more than one hundred alkaloids and synthetic compounds. The effects of these substances depend on their respective substituent. Natural β-carbolines prima ...

(present in tobacco tar) have been identified as comutagens.

References

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