Then, the study population was grouped according to the presence/absence of T2D and we observed that, among the obese subgroup (BMI>30 Kg/m2), patients with T2D had significantly higher apelin levels than non-diabetic subjects (1.62±1.43 ng/mL vs 0.97±0.78 ng/mL, P = 0.015), thus confirming the strong independent association of diabetes with apelin levels. The gene discussed is APLN; the disease is diabetes mellitus.