At 12 weeks, obesity and DEHP had reduced CAT levels to 88%, 90%, 89%, 83%, and 71% of the controls in the DEHP, DIO, DIO + DEHP low, DIO + DEHP middle, and DIO + DEHP high mice, respectively (P < 0.01). The gene discussed is CAT; the disease is obesity due to melanocortin 4 receptor deficiency.