CYP21A2
Chr 6cytochrome P450 family 21 subfamily A member 2
Also known as: CA21H, CAH1, CPS1, CYP21, CYP21B, P450c21B
This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This protein localizes to the endoplasmic reticulum and hydroxylates steroids at the 21 position. Its activity is required for the synthesis of steroid hormones including cortisol and aldosterone. Mutations in this gene cause congenital adrenal hyperplasia. A related pseudogene is located near this gene; gene conversion events involving the functional gene and the pseudogene are thought to account for many cases of steroid 21-hydroxylase deficiency. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]
Primary Disease Associations & Inheritance
Some data sources returned errors (1)
omim: Error: OMIM fetch failed: 429
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Typical tolerance to LoF variation
Mild missense constraint
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
CYP21A2 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
Solving Challenging Diagnoses Through Ultra-long Read Sequencing
ACTIVE NOT RECRUITINGA Study of Gene Therapy for Classic Congenital Adrenal Hyperplasia (CAH)
ACTIVE NOT RECRUITINGParenting and CAH - 21-hydroxylase Deficiency
RECRUITINGHydrocortisone Modified-release in Adults: Real-world Monitoring of Longitudinal Outcomes in coNgenital Adrenal hYperplasia
NOT YET RECRUITINGCombined Use of Machine Learning and Metabolomics to Improve the Diagnosis and Management of Hyperandrogenism
NOT YET RECRUITINGExternal Resources
Links to major genomics databases and tools