What makes aromatase

Learn more. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. Aromatase excess syndrome. From Genetics Home Reference. Description Aromatase excess syndrome is a condition characterized by elevated levels of the female sex hormone estrogen in both males and females.

Frequency The prevalence of aromatase excess syndrome is unknown; more than 20 cases have been described in the medical literature. Causes Rearrangements of genetic material involving the CYP19A1 gene cause aromatase excess syndrome. Inheritance This condition is inherited in an autosomal dominant pattern, which means a genetic rearrangement involving one copy of the CYP19A1 gene in each cell is sufficient to cause the disorder.

Molecular bases and phenotypic determinants of aromatase excess syndrome. Thus it is possible to envision tissue-specific inhibition of aromatase expression in a similar fashion to the concept of tissue-specific regulation of E action the concept of selective ER modulators. Specifically, drugs that target promoter II-driven expression of aromatase would be most useful because, in postmenopausal women, this promoter would appear to be exclusively used in tumor-containing breast tissue and in endometriotic plaques 27 , and thus bone in particular, which does not express promoter-II specific transcripts 28 , would be spared.

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Zeitoun K , Takayama K , Michael MD , Bulun SE Stimulation of aromatase promoter II activity in endometriosis and its inhibition in endometrium are regulated by competitive binding of steroidogenic factor-I and chicken ovalbumin upstram promoter transcription factor to the same cis-acting element.

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Br J Cancer 72 : — Cancer Lett : 27 — Epidemiology 7 : — Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. Sign In or Create an Account. Sign In. Advanced Search. Search Menu. Article Navigation. Close mobile search navigation Article Navigation.

Volume Aromatase EC 1. During aromatization reactions, aromatase forms an electron-transfer complex with its partner, NADPH-cytochrome P reductase. This enzyme is localized in the endoplasmic reticulum of the cell, and tissue specific promoters regulate its activity. The primary function of aromatase is to produce estrogens by aromatizing androgens.

Aromatase is the only known enzyme in vertebrates capable of catalyzing the aromatization of a six-membered ring [3]. Aromatase converts androstenedione to estrogen and testosterone to estradiol. This enzyme helps produce the female sex hormone, estrogen, that helps to fuel the growth of hormone receptor-positive breast cancer. There are many environmental factors that affect the activity of the aromatase enzyme and disrupt its function. Factors that increase the activity of the enzyme include age, obesity, gonadotropins, insulin, alcohol and smoking.

These features can appear as early as 12 weeks of pregnancy and go away soon after delivery. The prevalence of aromatase deficiency is unknown; approximately 20 cases have been described in the medical literature.

Mutations in the CYP19A1 gene cause aromatase deficiency. The CYP19A1 gene provides instructions for making an enzyme called aromatase. This enzyme converts a class of hormones called androgens, which are involved in male sexual development, to different forms of estrogen. In females, estrogen guides female sexual development before birth and during puberty.

In both males and females, estrogen plays a role in regulating bone growth and blood sugar levels. During fetal development, aromatase converts androgens to estrogens in the placenta, which is the link between the mother's blood supply and the fetus. This conversion in the placenta prevents androgens from directing sexual development in female fetuses. After birth, the conversion of androgens to estrogens takes place in multiple tissues.

CYP19A1 gene mutations that cause aromatase deficiency decrease or eliminate aromatase activity. A shortage of functional aromatase results in an inability to convert androgens to estrogens before birth and throughout life.

As a result, there is a decrease in estrogen production and an increase in the levels of androgens, including testosterone.