Recent study has revealed that the microbiota is subjected to variations in the host’s high triglycerides, fasting glucose and fasting insulin (Bhute et al., 2017), and metabolic disorders such as obesity (Turnbaugh et al., 2006) and diabetes (Qin et al., 2012; Karlsson et al., 2013) are found to be associated with microbial composition in which certain OTUs or species are present in different proportions. Here, INS is linked to obesity due to melanocortin 4 receptor deficiency.