Molecular genetics of human bone and mineral diseases, including juvenile Paget’s disease, metachondromatosis, hypophosphatasia, hypophosphatemic rickets, spondyloepiphyseal dysplasia tarda, and others. We study a variety of heritable bone diseases, identifying the genes and precise genetic mutations that cause these disorders, and examining how these mutations disrupt signaling pathways/bone turnover, to elucidate the pathobiology of these disorders.