Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted. The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit cc.nih.gov. Updates regarding government operating status and resumption of normal operations can be found at opm.gov.

NLM Logo

Steroid 21-Hydroxylase MeSH Descriptor Data 2026


MeSH Heading
Steroid 21-Hydroxylase
Tree Number(s)
D08.244.453.493.500
D08.244.453.915.760
D08.811.682.690.708.170.463.500
D08.811.682.690.708.170.915.760
D12.776.422.220.453.493.500
D12.776.422.220.453.915.760
Unique ID
D013255
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D013255
Scope Note
An adrenal microsomal cytochrome P450 enzyme that catalyzes the 21-hydroxylation of steroids in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP21 gene, converts progesterones to precursors of adrenal steroid hormones (CORTICOSTERONE; HYDROCORTISONE). Defects in CYP21 cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL).
Entry Term(s)
21-Hydroxylase
Cytochrome P-450 21-Hydroxylase
Cytochrome P-450 CYP21
Cytochrome P-450 c21
Cytochrome P-450(c-21)
Cytochrome P450c21
Progesterone 21-Hydroxylase
Steroid 21-Monooxygenase
Steroid-21-Hydroxylase
Registry Numbers
EC 1.14.14.16
CAS Type 1 Name
Steroid,hydrogen-donor:oxygen oxidoreductase (21-hydroxylating)
Previous Indexing
Steroid Hydroxylases (1973-1977)
Public MeSH Note
2003; see STE see STEROID 21-MONOOXYGENASE 1997-2002, see STEROID 21-HYDROXYLASE 1991-1996, see STEROID HYDROXYLASES 1978-1990; for STEROID 21-MONOOXYGENASE see STEROID 21-HYDROXYLASE 1978-1996; CYTOCHROME P-450 C21 was indexed under STEROID 21-HYDROXYLASE 2004 & under CYTOCHROME P-450 ENZYME SYSTEM 1996-2003
History Note
2003 (1978)
Entry Combination
deficiency:Adrenal Hyperplasia, Congenital
Date Introduced
1991/01/01
Last Updated
2016/06/01
Steroid 21-Hydroxylase Preferred
page delivered in 0.158s