Sensitive discrimination of stable mismatched base pairs by an abasic site modified fluorescent probe and lambda exonuclease.

An abasic site modified fluorescent probe has been developed which enabled the rapid discrimination of stable single mismatched base pairs by lambda exonuclease with remarkably high discrimination factors (447 for T:G and 238 for A:G). This method allowed sensitive detection of single nucleotide variation at very low abundances (0.02-0.05% mutant-to-wild type).