Important roles for uromodulin include protection against urinary tract infections by binding to type 1 – fimbriated uropathogenic E. coli3,4; reduction of kidney stone formation by binding calcium oxalate crystals5,6; and regulation of the Na+-cotransporters NKCC2 (SLC12A1) and NCC (SLC12A3) in the apical membrane of the TAL and DCT cells, respectively2,7,8. The gene discussed is SLC12A3; the disease is nephrolithiasis.