Exocyclic ethenobases are highly mutagenic DNA lesions strongly implicated in
inflammation and vinyl chloride-induced carcinogenesis. While the alkyladenine DNA
glycosylase, AAG (or MPG), binds the etheno lesions 1, N6-ethenoadenine (ɛA) and 3, N4-
ethenocytosine (ɛC) with high affinity, only ɛA can be excised to initiate base excision
repair. Here, we discover that the human AlkB homolog 2 (ALKBH2) dioxygenase enzyme
catalyzes direct reversal of ɛC lesions in both double-and single-stranded DNA with …