Vitamin D Hydroxylation-Deficient Rickets, Type 1b, also known as vitamin d-dependent rickets type 1b, is related to vitamin d-dependent rickets and vitamin d hydroxylation-deficient rickets, type 1a, and has symptoms including muscle weakness, bone pain and difficulty standing. An important gene associated with Vitamin D Hydroxylation-Deficient Rickets, Type 1b is CYP2R1 (Cytochrome P450 Family 2 Subfamily R Member 1), and among its related pathways/superpathways are Metabolism of steroids and Vitamin D receptor pathway. The drugs Hydroxocobalamin and Iron have been mentioned in the context of this disorder. Affiliated tissues include bone and kidney, and related phenotypes are hypophosphatemia and hypocalcemia