CYP2E1 and obesity due to melanocortin 4 receptor deficiency: One CYP2E1 restriction fragment length polymorphism (RFLP) (CYP2E1*1D) has been shown to have a higher prevalence in women of African ancestry, and functional impact on in vivo metabolic activity in the presence of exposures known to increase expression of CYP2E1 [obesity or recent (within 72 h) alcohol consumption] [56].