Rankin W et al. in their review on PTH-rP and hypercalcemia have mentioned that the receptor binding and activation domains of PTH and PTH-rP are present with in the first 34 amino acids and both the hormones have identical actions of inducing hypercalcemia by promoting bone resorption and decreasing calcium excretion.[10] Hypercalcemia can induce clinical manifestations like central nervous system depression, muscular weakness, cardiac abnormalities, gastrointestinal disturbances and renal failure. Here, BLOC1S3 is linked to hypercalcemia disease.