SO42− uptake was competitively inhibited by Ox2− (Ki of 63.5 μM), a value close to the oxalate concentration detected in the serum of patients with hyperoxaluria or end-stage renal disease, whereas oxalate uptake showed saturation kinetics with a Km of 53.5 μM, a value close to that obtained for the Ki for competitive inhibition of SO42− uptake by Ox2− (63.5 μM), indicating an interaction at the same site of SLC26A1 (Krick et al., 200). The gene discussed is SLC26A1; the disease is Hyperoxaluria.