ERCC2 and pachyonychia congenita: In addition, Nakao et al indicated no significant associations between OGG1 Ser326Cys polymorphism and PC risk in Asians.[17] Subgroup study indicated significant associations between ERCC2 rs13181 polymorphism and PC risk in Asians, whereas the associations were not obvious between ERCC2 rs13181 polymorphism and PC risk in Caucasians.