The association of rs13283416 with multiple components of metabolic syndrome (clustering of increased blood pressures and obesity with dyslipidaemia and diabetes (https://www.nhs.uk/conditions/metabolic-syndrome/, accessed on 28 July 2021) is noteworthy: because of the growing evidence of firstly, a bi-directional relationship between the brain and metabolic systems [36] and secondly, the overlap in genetic regulation of eating disorders such as anorexia nervosa and insulin signalling [37] (widely considered to be the underlying process linking metabolic syndrome components). Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.