AXIN2 and Oligodontia: In contrast, AXIN2 rs2240308 showed association with hypodontia in individuals from Brazil who had at least one missing tooth, although one conclusion of this study was that dental agenesis arises from multiple AXIN2 gene variants.37 Mutations in AXIN2 have been mainly associated with moderate oligodontia which affects incisors and also individuals with severe oligodontia which is caused by two truncated AXIN2 proteins.4,38