SLC12A3 and familial primary hypomagnesemia: Gitelman syndrome (GS) is a tubulopathy characterized by hypokalemic metabolic alkalosis in combination with significant hypomagnesemia and hypocalciuria, which is an autosomal recessive disease primarily caused by mutations in SLC12A3 gene.[1] GS is one of the most common causes of inherited hypokalemia and is a highly heterogeneous disease.