In addition, patients with enchondromatosis (Ollier disease and Maffucci syndrome, OMIM 166000) carry mutations in parathyroid hormone-related protein (PTHrP) receptor (Pthr)1 [11], while mice with the Pthr1 R150C mutation exhibit constitutive activation of HH signaling and develop multiple enchondroma-like lesions [11,12]. The gene discussed is PTHLH; the disease is Ollier disease.