Notably, kidney tissue has high expression levels of TRPM3, particularly in the medullary ray, the renal corpuscle, and the epithelium of the collecting tubule, suggesting its potential role in the resorption of calcium and other divalent ions.6,23 This hypothesis explains the hypercalciuria, hypocalcemia, and hypomagnesemia observed in our patient. Here, TRPM3 is linked to familial primary hypomagnesemia.