Deamination mutagenesis

(a) Loss of an amine (NH2) group changes C to U, which will pair with A.

(b) Methylation of bases is one form of post-replication modification that marks bases as newly-replicated. Methylated C bases (mC) can also be deaminated to T, which will pair with A.

Figure ©2000 by Griffiths et al. ; text ©2014 by Steven M. Carr