In terms of VNTR polymorphism (40 base pairs) in the DAT gene (DAT1/SLCA3: NC_000005.10 (1392794-1445440), complement), individuals with the nine-repeat allele (9R), associated with increased DAT1 expression [39], correlate with an increased risk for obesity compared with individuals with ten-repeat allele (10R) [40,41]. This evidence concerns the gene SLC6A3 and obesity due to melanocortin 4 receptor deficiency.