Furthermore, the NK cell maturation state was also changed between AP and NP mice, with obesity combined with AP driving the dNK cell differentiation from immature CD11b−CD27− or CD11b−CD27+ to relatively mature CD11b+CD27+ phenotypes and prevented further maturation into the CD11b+CD27− subset. The gene discussed is CD27; the disease is obesity due to melanocortin 4 receptor deficiency.