Twelve months after BS, serum CSTA levels were markedly decreased (1.64 ± 0.17 vs. 3.47 ± 0.36 ng/mL at baseline, p < 0.0001) (Fig. 6B), strongly suggesting that CSTA platelet levels increase during obesity and are further stimulated by T2DM. The gene discussed is CSTA; the disease is obesity due to melanocortin 4 receptor deficiency.