Alkylation Mutagenesis

Alkylation (addition of a methyl or ethyl group) of the 6'-O position in guanine leaves only two sites for H-bonds: O-6-ethyl-G pairs with T instead of C.

Ethyl Methane Sulfonate (EMS) is commonly use to mutagenize Drosophila and other laboratory organisms, since it can be incorporated directly into food.

Figure © 2000 by Griffiths et al. ; text © 2010 by Steven M. Carr