Pathophysiology of 17α hydroxylase deficiency
17α Hydroxylase (P450c17) is the enzyme responsible for the biosynthetic step that converts mineralocorticoids to glucocorticoids (17α-hydroxylase activity) and glucocorticoids to sex steroids (17,20-lyase activity). More than 20 mutations have been identified on CYP17, the gene on chromosome 10 that encodes 17α-hydroxylase.
Abnormal enzyme activity can be manifested as isolated 17α-hydroxylase deficiency, 17,20-lyase deficiency, or their combination. Inadequate 17α-hydroxylase activity leads to inadequate cortisol production, excessive effects of corticotropin, and increased levels of DOC. In contrast to 11β-hydroxylase deficiency, sex steroid production is decreased.
