Autosomal recessive hypophosphatemic rickets (ARHR) is a rare form of hypophosphatemic rickets that is caused by mutations in the DMP1 gene. DMP1 is highly expressed in mineralized tissues, especially in osteoblasts and osteocytes, and is a key regulatory protein that is required for the normal growth and development of bone, cartilage and dentin. Recently, ARHR associated with a mutation in the ENPP1 gene has also been reported.
