Therefore, the aim of this study was to screen for genetic variations of two single-nucleotide polymorphisms (SNPs), FokI (rs2228570) and BsmI (rs1544410), of the VDR gene in a well-defined population of individuals with PC and compare their incidence with that of a healthy control population, in order to determine the contribution of VDR polymorphisms to PC in North China. The gene discussed is VDR; the disease is pachyonychia congenita.