SIRT1 and obesity due to melanocortin 4 receptor deficiency: It has been reported that SIRT1 rs2273773 is associated with Rheumatoid Arthritis (RA), chronic obstructive pulmonary disease (COPD) [25]; rs7069102 is associated with COPD [25], cardiovascular diseases (CVD) [26], and myocardial infarction [27]; rs7895833 is associated with COPD [25], lifespan longevity [28], and obesity [29]; rs4746720 is associated with Type 2 Diabetes Mellitus [30].