It has been reported that in obesity there is an increased frequency of pro-inflammatory CD4+ T cells (e.g., Th1 and Th17 cells), and cytotoxic CD8+ T cells, and reduction in anti-inflammatory CD4+ T cells (e.g., Th2 cells) and FOXp3 regulatory T cells (Tregs) (55). This evidence concerns the gene CD4 and obesity due to melanocortin 4 receptor deficiency.