The two main categories of mechanisms linked to hypercalcaemia are those mediated by PTH (primary and tertiary hyperparathyroidism, familial benign hypocalciuric hypercalcaemia, Lithium induced hypercalcaemia, etc.)and those mediated by non-PTH (associated to production of calcitriol, PTH related protein, or cytokines as mediators) (1). The gene discussed is PTH; the disease is Hypercalcemia.