The vitamin D receptor (VDR) is a ligand-activated transcription factor, and recent analysis of VDR genome-wide occupancy using ChIP-seq revealed that loci associated by GWAS in several autoimmune conditions including IRF8 (associated with MS) and PTPN2 (Crohn's disease and T1D) were bound by VDR [69]. Here, VDR is linked to type 1 diabetes mellitus.