Thus, despite little differences in GTT and ITT, the fasting insulin levels of C57BL/6JRj on WD suggest an absence of hyperinsulinemia compared to C57BL/6JBomTac and C57BL/6J which complies with C57BL/6JRj being less susceptible to WD induced obesity. This evidence concerns the gene INS and obesity due to melanocortin 4 receptor deficiency.