The repair of oxidative adduct 8-oxo-guanine (8-oxoG) by the 8-oxo-guanine DNA glycosylase 1 (OGG1) has been implicated in CAG/CTG repeat expansions, as depleting Ogg1 abolishes age-dependent CAG repeat expansion in HD mouse models (16). The gene discussed is OGG1; the disease is Huntington disease.