It is also undefined which other factors, including gender, age, alcohol consumption, obesity, and urate transporter genes regulating renal absorption of UA, e.g., SLC22A12 [22], SLC2A9/GLUT9 [23], and ABCG2 [24,25], are key factors for UA-dependent lung function. The gene discussed is SLC2A9; the disease is obesity due to melanocortin 4 receptor deficiency.