NTRK2 and obesity due to melanocortin 4 receptor deficiency: Notably, ChrSd supplementation lowered the hepatic expression of genes previously reported to be candidate genes for obesity, such as Insig-1 [26], lepR [27], neurotrophic tyrosine kinase receptor type 2 (Ntrk2) [28], melanocortin 5 receptor (Mc5r) [29], and matrix metallopeptidase 7 (Mmp7) [30].