Expression of Il33 and ST2 has also been reported to be increased in adipose tissue of obese mice and humans10, while the number of ST2-expressing cell has been reported to be reduced in WAT in obese animal models11,31, illustrating possible yet unresolved issues regarding IL-33 and its influence on WAT metabolism in homeostatic conditions and during obesity development. The gene discussed is IL33; the disease is obesity due to melanocortin 4 receptor deficiency.