Hypercalcemia leads to renal dysfunction by various mechanisms, such as renal hypoperfusion due to vasoconstriction of the afferent arteriole, hypovolemia as a consequence of sodium and water spoliation due to blockage of the Na-K-ATPase pump, dysfunction of urinary concentration mechanisms due to decreased sensitivity to antidiuretic hormone, and acute tubular necrosis resulting from intracellular calcium overload and obstruction of the renal tubules. The gene discussed is AVP; the disease is hypercalcemia disease.