In the present work, we focussed on the closest TRPM7 relative, TRPM6, because loss-of-function mutations in TRPM6 cause hypomagnesemia (low Mg2+ blood levels) in human infants thought to mainly result from renal Mg2+ wasting (Schlingmann et al., 2002; Walder et al., 2002; Voets et al., 2004). This evidence concerns the gene TRPM6 and familial primary hypomagnesemia.