MTHFR and pachyonychia congenita: Similarly, we determined the most optimal genetic models to correlate with PC risk for ABO rs495828, FTO rs9939609, CDKN2A/B rs2518719, XRCC4 rs2075685, XRCC1 rs25487, XPC rs2607775, MORC4 rs12837024, VEGF +405 rs2010963, and MTHFR rs1801133 using the criteria of FPRP value < 0.2 as indicating significant PC risk.