Aromatase (ARO)

Aromatase is an enzyme that is responsible for a key step in the biosynthesis of estrogens. Because estrogens also promote certain cancers and other diseases, aromatase inhibitors are frequently used to treat those diseases.

This protein localizes to the endoplasmic reticulum and catalyzes the last steps of estrogen biosynthesis from androgens. These steps include three successive hydroxylations of the 19-methyl group of androgens followed by simultaneous elimination of the methyl group as formate and aromatization of the A-ring. Mutations in this gene can result in either increased or decreased aromatase activity; the associated phenotypes suggest that estrogen functions both as a sex steroid hormone and in growth or differentiation. The gene expresses two transcript variants.