UMOD and autosomal dominant medullary cystic kidney disease with or without hyperuricemia: Mutations in the uromodulin (UMOD) gene cause autosomal dominant kidney diseases, medullary cystic kidney disease 2 (MCKD2), and familial juvenile hyperuricemic nephropathy (FJHN), which present with juvenile onset of polyuria, hyperuricemia, gout, and progressive nephropathy [4].