Approximately 8-10% of cases of patients with Ollier disease have been linked to PTH1R mutations. A particular case study the mutant heterozygous PTHR1 (R150C) receptor was observed in two unrelated patients with Ollier disease. This PTHR1 (R150C) mutant causes a reduction in chondrocyte differentiation by triggering the PTHrP-dependent pathway and decreasing PTHLH receptor function by approximately 30% creating enchondromas. One of these patients with the PTHR1 (R150C) mutant was found to have inherited the mutation from his father. This provides credence to the theory that multiple genetic mutations are needed to occur in order for Ollier disease to manifest.