Background Hyperuricemia induces common diseases, gout and kidney stones, and accelerates the progression of renal diseases. Hyperuricemia has been clinically classified into the urate overproduction type (the renal urate overload type) including the extra-renal urate underexcretion type, the renal underexcretion type, and the combined type. We have reported that the dysfunction of ATP-binding cassette transporter, sub-family G, member 2 (ABCG2) is the major cause of hyperuricemia, especially extra-renal urate underexcretion type hyperuricemia. But its involvement in renal underexcretion type hyperuricemia, the most prevalent subtype, is not clearly explained so far.
Objectives The aim of present study is to determine the contribution of ABCG2 to the onset of each type of hyperuricemia.
Methods We performed the association analysis with hyperuricemia patients and controls in male Japanese.
Results ABCG2 dysfunction significantly increased the risk of the whole hyperuricemia and renal urate overload type hyperuricemia, according to the severity of impairment. Furthermore, slight and moderate ABCG2 dysfunction significantly increased the risk of renal underexcretion type hyperuricemia. ABCG2 dysfunction caused renal urate underexcretion and induced hyperuricemia even if the renal urate overload was not remarkable.
Conclusions These results show that ABCG2 plays physiologically important roles in both renal and extra-renal urate excretion mechanisms.
Matsuo H, Takada T, Ichida K, et al: Common defects of ABCG2, a high-capacity urate exporter, cause gout: a function-based genetic analysis in a Japanese population. Sci Transl Med 1:5ra11, 2009
Ichida K, Matsuo H, Takada T, et al: Decreased extra-renal urate excretion is a common cause of hyperuricemia. Nat Commun 3:764, 2012
Matsuo H, Nakayama A, Sakiyama M, et al: ABCG2 dysfunction causes hyperuricemia due to both renal urate underexcretion and renal urate overload. Sci Rep 4:3755, 2014
Disclosure of Interest None declared