FTO and obesity due to melanocortin 4 receptor deficiency: Interestingly, recent findings indicate that activation of IRX3 in macrophages may control body weight through promoting transcription of proinflammatory cytokines and repression of adipocyte adrenergic signaling9; and transgenerational inheritance of obesity is regulated by activation of IRX3 in hypothalamic neurons by enhancers localized in intron 8 of FTO. 10