ABCG2 and obesity due to melanocortin 4 receptor deficiency: In addition to the several risk factors for gout reported by Hippocrates 2500 years ago [2], i.e., sex, obesity, alcohol consumption, and aging, we and other researchers revealed that common dysfunctional variants of ABCG2/BCRP gene, encoding a high-capacity urate exporter, are significant genetic causes of gout and hyperuricemia [3–5].