MUTYH (MYH) functions as an adenine DNA glycosylase and removes adenines and 2-hydroxyadenines on the newly synthesized DNA strand mispaired with guanines or 8-oxoguanines on the template strand (Ohtsubo et al. 2000, Boldogh et al. 2001). Under physiological conditions, the preferred substrate for both MUTYH isoforms, MUTYH-3 (alpha-3) and MUTYH-6 (gamma-3) is adenine mispaired with 8-oxoguanine (OGUA:Ade) (Shinmura et al. 2000).