A significant increase in the claudin-2 mRNA in the ileum (Figure 3f), an increase of FITC-dextran (Figure 3g) and an increase of endotoxin—LPS (Figure 3h), although not significant, in the serum of obese and infected compared to lean and infected mice suggests the augmentation of intestinal permeability in the comorbidity of obesity and TB. The gene discussed is CLDN2; the disease is obesity due to melanocortin 4 receptor deficiency.