ABCG2 and obesity due to melanocortin 4 receptor deficiency: Linear regression analysis showed that the mean sUA level increased linearly with the number of risk alleles of the three candidate genetic variants (Beta = 0.18, p = 1.94 × 10− 12) The joint effect of the ABCG2 rs2231142 T allele and cardiovascular risk factors (obesity, hypertension and dyslipidemia) was also associated with increased HUA risk and sUA levels.