Numerous genetic association studies have suggested that these variants may modulate the risk of developing heart failure, asthma and airway hyper-responsiveness, protection from traumatic or septic shock, obesity, and cancer, where β2AR plays a central role.10, 11, 12, 13, 14 Nevertheless, data often lead to conflicting mechanistic explanations, likely relating to the complex and heterogenic nature of the ADRB2 locus.15 Here, ADRB2 is linked to obesity due to melanocortin 4 receptor deficiency.