DHCR7 and rheumatoid arthritis: In addition to RA onset, Viatte et al. further examined 20 SNPs (rs6013897, rs17217119, rs10500804, rs1993116, rs10741657, rs7116978, rs127947147, rs127858787, rs12800438, rs4944076, rs4944997, rs7944926, rs4945008, rs3829251, rs2298850, rs3755967, rs2282679, rs1155563, rs17467825, rs7041) from four vitamin D metabolism genes (GC, DHCR7/NADSYN1, CYP2R1, and CYP24A1) with RA radiological outcome, as reflected by Larsen score and presence of erosion.