SLC22A12 and obesity due to melanocortin 4 receptor deficiency: Differential gene expression of ABCG2, SLC22A12, IL-1β, and ALPK1 in peripheral blood leukocytes of primary gout patients (chronic or acute) correlated with hyperuricemia and its comorbidities, such as dyslipidemia, obesity, hypertension, metabolic syndrome, kidney disease, and high levels of creatinine in blood.