ESPE Abstracts

Background: Cytochromes P450 proteins metabolize several steroid hormones, drugs and xenobiotics. All cytochromes P450s in the endoplasmic reticulum require P450 oxidoreductase (POR) for their catalytic activities. Earlier it has been shown that mutations in POR cause metabolic disorders of steroid hormone biosynthesis and also affect some drug metabolizing P450 activities. We aimed to characterize the mutations identified in nonclinical samples to access their effects on ster...

Background: P450 oxidoreductase (POR) mutations can present with disordered sexual development (46,XX virilisation as well as 46,XY under-masculinisation), perturbed steroidogenesis and mild to severe skeletal malformations. As POR is an obligate electron donating cofactor to many P450s, and as this interaction may vary from partner to partner, the phenotypic spectrum of PORD is extremely broad. Therefore, to characterize novel POR mutations, specific testing is required.<...

Background: Cytochrome P450 oxidoreductase (POR) deficiency (PORD) is a form of congenital adrenal hyperplasia (CAH) and results in steroid-production loss from cytochrome P450 proteins. Mutations in POR cause mild to severe forms of CAH with/without bone malformation symptoms resembling Antley-Bixler syndrome. We report a novel POR Arg550Trp mutation identified in a 46,XX patient with signs of aromatase (ARO) deficiency. Child (first pregnancy) and mother pr...