The patient had compound heterozygous mutations in the hURAT1 gene (R90H and W258X), but showed no clinical manifestations such as urolithiasis or exercise-induced acute renal failure.
Recent identification of the urate transporter in the kidney (URAT1, encoded by SLC22A12) led to the molecular elucidation of idiopathic renal hypouricemia, which is a predisposition toward exercise-induce acute renal failure.