NADSYN1 and rheumatoid arthritis: They selected three genome-wide significant vitamin D-associated independent SNPs located in SSTR4 (rs2207173), GC (rs2282679), and NADSYN1 (3829251) as IVs and applied these IVs on information from a meta-GWAS of 5539 autoantibody-positive RA patients and 20,169 controls, all of European ancestry.