VDR and type 1 diabetes mellitus: One case report describes the development of T1D in a child with pre-existing hereditary vitamin D-resistent rickets (VDRR) due to a compound heterozygous mutation of the VDR (L263R and R391S) that led to dissociated responses of the CYP24A1 and RELB promoters to 1,25-Dihydroxyvitamin D3 action [84].