MCT1 haploinsufficient (MCT1+/−) mice are resistant to the development of obesity and the appearance of hepatic steatosis when fed a high fat diet as well as to the development of chronic hepatic inflammation as indicated by the absence of TNFα mRNA induction under HFD (Supplementary Figure 1A–E). This evidence concerns the gene TNF and obesity due to melanocortin 4 receptor deficiency.