SDC4 and obesity due to melanocortin 4 receptor deficiency: After inducing obesity in Sdc4-deficient (Sdc4−/−) and wild-type (WT) mice by feeding the animals a high-fat diet (HFD), we observed that female Sdc4−/− mice, but not males, displayed increased adiposity, higher fasting levels of plasma total cholesterol (TC), triglyceride (TG), and glucose, and lower insulin sensitivity than WT [20].