Adenine glycosylase active on G-A mispairs. MutY also corrects error-prone DNA synthesis past GO lesions which are due to the oxidatively damaged form of guanine: 7,8-dihydro-8-oxoguanine (8-oxo-dGTP). Hydrolyzes free adenine bases from 7,8-dihydro-8-oxoguanine:adenine mismatched double-stranded DNA, leaving an apurinic site. Binds 1 [4Fe-4S] cluster. The cluster does not appear to play a role in catalysis, but is probably involved in the proper positioning of the enzyme along the DNA strand. Monomer. Belongs to the Nth/MutY family.