CYP17A1 and obesity due to melanocortin 4 receptor deficiency: Cytochrome P450, family 17, subfamily A, polypeptide 1 (Cyp17A1), a member of the CYP450 family, is implicated in cholesterol, steroids and other lipid responses, and their relationship with obesity has been previously reported (Mathews et al. 2014; Rosen et al. 1989; Tabur et al. 2016; Yousefi et al. 2011).