Examples of Some Useful Mutagens

Mutagens are chemical or physical agents that increase the frequency of mutations. Essentially all mutagens show some specificity for the type of mutations produced. The following table indicates the type of mutations typically produced by some useful mutagens.

MutagenMechanismTypes of mutations produced
SpontaneousDNA replication and repair errors, spontaneous modification of nucleotidesAll types of mutations produced
UV irradiationPyrimidine dimers induce error prone repair (SOS) Mainly G-C to A-T transitions, but all other types of mutations including deletions, frameshifts, and rearrangements at somewhat lower frequency
2-aminopurine (2AP)Base analogA-T to G-C and G-C to A-T transitions
BromouracilBase analog G-C to A-T and A-T to G-C transitions
Hydroxylamine (NH2OH)Alkylating agent, generates N4-hudroxycytosine G-C to A-T transitions when used in vitro
N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)Alkylating agent, generates O6-methylguanineG-C to A-T transitions, multiple, closely spaced mutations common
Ethylmethane sulfonate (EMS) (EMS)Alkylating agent, generates O6-methylguanineG-C to A-T transitions
Ethylethane sulfonate (DES)Alkylating agent, induces SOS responseG-C to T-A transversions, other base substitution mutations
Nitrous acidOxidative deaminationG-C to A-T and A-T to G-C transitions, deletions produced at a lower frequency
ICR-191Intercalating agent, alkylacridine derivative that stabilizes looped out bases by stacking between themFrameshifts, mainly additions or deletions in runs of G or C


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Last modified July 15, 2002