Cytochrome b5 deficiency
Cytochrome b5 deficiency is a rare condition and form of isolated 17,20-lyase deficiency caused by deficiency in cytochrome b5, a small hemoprotein that acts as an allosteric factor to facilitate the interaction of CYP17A1 (17α-hydroxylase/17,20-lyase) with P450 oxidoreductase (POR), thereby allowing for the 17,20-lyase activity of CYP17A1.[1][2][3] The condition affects both adrenal and gonadal androgen biosynthesis and results in male pseudohermaphroditism.[1] The principal biological role of cytochrome b5 is reduction of methemoglobin, so cytochrome b5 deficiency can also result in elevated methemoglobin levels and/or methemoglobinemia, similarly to deficiency of cytochrome b5 reductase (methemoglobin reductase).[1] This article about an endocrine, nutritional, or metabolic disease is a stub.You can help Wikipedia by expanding it.