ENPP1 and autosomal recessive hypophosphatemic rickets: Autosomal Recessive Hypophosphatemic Rickets (ARHR) type 1 (MIM 241520) and 2 (MIM 613312) are associated with molecular defects in Dentin matrix protein 1 (DMP1) and the ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1), respectively [152,153].