Synthetic defect in CYP21A2 (21-hydroxylase) deficiency
Synthetic defect in CYP21A2 (21-hydroxylase) deficiency
Pathways of adrenal steroid synthesis. A synthetic defect in 21-hydroxylase leads to diminished cortisol synthesis, increased release of corticotropin (ACTH), accumulation of 17-hydroxyprogesterone (particularly after the administration of ACTH), possible virilization due to increased androgen production, and possible salt wasting due to diminished production of aldosterone and deoxycorticosterone.
The numbers at the arrows refer to specific enzymes: 17α: 17α-hydroxylase (P450c17); 17,20: 17,20 lyase which is part of the P450c17 enzyme; 3β: 3β-hydroxysteroid dehydrogenase; 21: 21-hydroxylase (P450c21); 11β: 11β-hydroxylase; (P450c11); 18 refers to the two-step process of aldosterone synthase (P450c11as), resulting in the addition of an hydroxyl group that is then oxidized to an aldehyde group at the 18-carbon position; ?: unclear if pathway functions in vivo; DHEA: dehydroepiandrostenedione; 17KSR: 17-ketosteroid reductase; and A: aromatase.
