Although the role of TGF-β1 in the context of obesity-induced airway fibrosis in asthma remains elusive, and one study observed no difference in serum levels of TGF-β1 between individuals with asthma and obesity compared to healthy controls (243), the role of TGF-β1 in the context of obesity-induced airway fibrosis should be considered. The gene discussed is TGFB1; the disease is obesity due to melanocortin 4 receptor deficiency.