CYP11B2

Reviewed November 2010

What is the official name of the CYP11B2 gene?

The official name of this gene is “cytochrome P450, family 11, subfamily B, polypeptide 2.”

CYP11B2 is the gene's official symbol. The CYP11B2 gene is also known by other names, listed below.

What is the normal function of the CYP11B2 gene?

The CYP11B2 gene provides instructions for making an enzyme called aldosterone synthase. This enzyme is found in the adrenal glands, which are located on top of the kidneys. Aldosterone synthase is a member of the cytochrome P450 family of enzymes. These enzymes are involved in many processes in the body.

Aldosterone synthase helps produce a hormone called aldosterone. Aldosterone helps control blood pressure by maintaining proper salt and fluid levels in the body. The aldosterone synthase enzyme is involved in a series of three chemical reactions that produce aldosterone: the conversion of 11-deoxycorticosterone to corticosterone, the conversion of corticosterone to 18-hydroxycorticosterone, and the conversion of 18-hydroxycorticosterone to aldosterone.

Does the CYP11B2 gene share characteristics with other genes?

The CYP11B2 gene belongs to a family of genes called CYP (cytochrome P450).

A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genefamilies) in the Handbook.

How are changes in the CYP11B2 gene related to health conditions?

familial hyperaldosteronism - increased risk from variations of the CYP11B2 gene

The genetic change responsible for familial hyperaldosteronism type I fuses the section of the CYP11B2 gene that contains the instructions for making aldosterone synthase to a section of a nearby gene called CYP11B1. The added part of the CYP11B1 gene contains a section called a promoter region, which normally starts the production of the 11-beta-hydroxylase enzyme from the CYP11B1 gene. As part of the fused gene, the CYP11B1 gene's promoter region instead starts the production of aldosterone synthase from the CYP11B2 gene.

The activity of the CYP11B1 gene's promoter region is triggered by a hormone called adrenocorticotropic hormone (ACTH). As a result of the fused gene, aldosterone synthase activity is abnormally responsive to ACTH levels, resulting in excessive amounts of aldosterone being produced. The excessive aldosterone production leads to the high blood pressure (hypertension) associated with familial hyperaldosteronism type I.

other disorders - caused by mutations in the CYP11B2 gene

Mutations in the CYP11B2 gene also cause two forms of corticosterone methyloxidase deficiency: type I, which is found in the Amish community, and type II, which has been identified in the Iranian Jewish population. CYP11B2 gene mutations associated with corticosterone methyloxidase deficiency interfere with the step of aldosterone synthesis in which corticosterone is converted to 18-hydroxycorticosterone. Individuals with corticosterone methyloxidase deficiency produce little or no aldosterone and lose large amounts of sodium in their urine, which can be life-threatening.

Where is the CYP11B2 gene located?

Cytogenetic Location: 8q21-q22

Molecular Location on chromosome 8: base pairs 143,991,974 to 143,999,258

The CYP11B2 gene is located on the long (q) arm of chromosome 8 between positions 21 and 22.

More precisely, the CYP11B2 gene is located from base pair 143,991,974 to base pair 143,999,258 on chromosome 8.

See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.

Where can I find additional information about CYP11B2?

You and your healthcare professional may find the following resources about CYP11B2 helpful.

Educational resources - Information pages
Endocrinology (2001): Synthesis of the major steroid hormones secreted by the adrenal cortex (http://www.ncbi.nlm.nih.gov/books/NBK26/?rendertype=box&id=A463)
Genetic Testing Registry - Repository of genetic test information
- GTR: Genetic tests for CYP11B2 (http://www.ncbi.nlm.nih.gov/gtr/tests/?term=1585%5Bgeneid%5D)

You may also be interested in these resources, which are designed for genetics professionals and researchers.

PubMed - Recent literature (http://www.ncbi.nlm.nih.gov/pubmed?term=(CYP11B2%5BTIAB%5D)%20AND%20((Genes%5BMH%5D)%20OR%20(Genetic%20Phenomena%5BMH%5D))%20AND%20english%5Bla%5D%20AND%20human%5Bmh%5D%20AND%20%22last%201080%20days%22%5Bdp%5D)
OMIM - Genetic disorder catalog
- CORTICOSTERONE METHYLOXIDASE TYPE I DEFICIENCY (http://omim.org/entry/203400)
- CORTICOSTERONE METHYLOXIDASE TYPE II DEFICIENCY (http://omim.org/entry/610600)
- CYTOCHROME P450, SUBFAMILY XIB, POLYPEPTIDE 2 (http://omim.org/entry/124080)
Research Resources - Tools for researchers
- Atlas of Genetics and Cytogenetics in Oncology and Haematology (http://atlasgeneticsoncology.org/Genes/GC_CYP11B2.html)
- Entrez Gene (http://www.ncbi.nlm.nih.gov/gene/1585)
- GeneCards (http://www.genecards.org/cgi-bin/carddisp.pl?id_type=entrezgene&id=1585)
- HUGO Gene Nomenclature Committee (http://www.genenames.org/data/hgnc_data.php?hgnc_id=2592)

What other names do people use for the CYP11B2 gene or gene products?

ALDOS
aldosterone synthase
aldosterone-synthesizing enzyme
C11B2_HUMAN
CPN2
CYP11B
CYP11BL
CYPXIB2
cytochrome P450 11B2, mitochondrial
cytochrome P450 11B2, mitochondrial precursor
cytochrome P-450Aldo
cytochrome P-450C18
cytochrome P450, subfamily XIB (steroid 11-beta-hydroxylase), polypeptide 2
mitochondrial cytochrome P450, family 11, subfamily B, polypeptide 2
P450aldo
P450C18
P-450C18
steroid 11-beta/18-hydroxylase
steroid 11-beta-monooxygenase
steroid 18-hydroxylase, aldosterone synthase, P450C18, P450aldo

See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.

What glossary definitions help with understanding CYP11B2?

adrenal glands ; aldosterone ; cytochrome P450 ; deficiency ; enzyme ; familial ; gene ; hormone ; hypertension ; population ; promoter ; promoter region ; sodium ; synthesis

You may find definitions for these and many other terms in the Genetics Home Reference Glossary (http://www.ghr.nlm.nih.gov/glossary).

References

Entrez Gene (http://www.ncbi.nlm.nih.gov/gene/1585)
Martinez-Aguayo A, Fardella C. Genetics of hypertensive syndrome. Horm Res. 2009;71(5):253-9. doi: 10.1159/000208798. Epub 2009 Apr 1. Review. (http://www.ncbi.nlm.nih.gov/pubmed/19339789?dopt=Abstract)
OMIM: CYTOCHROME P450, SUBFAMILY XIB, POLYPEPTIDE 2 (http://omim.org/entry/124080)
Quack I, Vonend O, Rump LC. Familial hyperaldosteronism I-III. Horm Metab Res. 2010 Jun;42(6):424-8. doi: 10.1055/s-0029-1246187. Epub 2010 Feb 3. Review. (http://www.ncbi.nlm.nih.gov/pubmed/20131203?dopt=Abstract)
Stowasser M, Gordon RD. Familial hyperaldosteronism. J Steroid Biochem Mol Biol. 2001 Sep;78(3):215-29. Review. (http://www.ncbi.nlm.nih.gov/pubmed/11595502?dopt=Abstract)
Stowasser M, Gordon RD. Monogenic mineralocorticoid hypertension. Best Pract Res Clin Endocrinol Metab. 2006 Sep;20(3):401-20. Review. (http://www.ncbi.nlm.nih.gov/pubmed/16980202?dopt=Abstract)
Stowasser M, Gunasekera TG, Gordon RD. Familial varieties of primary aldosteronism. Clin Exp Pharmacol Physiol. 2001 Dec;28(12):1087-90. Review. (http://www.ncbi.nlm.nih.gov/pubmed/11903322?dopt=Abstract)
Torpy DJ, Stratakis CA, Chrousos GP. Familial hyperaldosteronism. Braz J Med Biol Res. 2000 Oct;33(10):1149-55. Review. (http://www.ncbi.nlm.nih.gov/pubmed/11004715?dopt=Abstract)
White PC. Aldosterone synthase deficiency and related disorders. Mol Cell Endocrinol. 2004 Mar 31;217(1-2):81-7. Review. (http://www.ncbi.nlm.nih.gov/pubmed/15134805?dopt=Abstract)
Williams SS. Advances in genetic hypertension. Curr Opin Pediatr. 2007 Apr;19(2):192-8. Review. (http://www.ncbi.nlm.nih.gov/pubmed/17496764?dopt=Abstract)

The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.