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GTR Home > Conditions/Phenotypes > Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Synonyms
21-Hydroxylase-Deficient Congenital Adrenal Hyperplasia; CYP21 deficiency; Congenital adrenal hyperplasia due to 21-hydroxylase deficiency
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

Excerpted from the GeneReview: 21-Hydroxylase-Deficient Congenital Adrenal Hyperplasia
21-hydroxylase deficiency (21-OHD) is the most common cause of congenital adrenal hyperplasia (CAH), a family of autosomal recessive disorders involving impaired synthesis of cortisol from cholesterol by the adrenal cortex. In 21-OHD CAH, excessive adrenal androgen biosynthesis results in virilization in all individuals and salt wasting in some individuals. A classic form with severe enzyme deficiency and prenatal onset of virilization is distinguished from a non-classic form with mild enzyme deficiency and postnatal onset. The classic form is further divided into the simple virilizing form (~25% of affected individuals) and the salt-wasting form, in which aldosterone production is inadequate (≥75% of individuals). Newborns with salt-wasting 21-OHD CAH are at risk for life-threatening salt-wasting crises. Individuals with the non-classic form of 21-OHD CAH present postnatally with signs of hyperandrogenism; females with the non-classic form are not virilized at birth.
Full text of GeneReview (by section):
Summary
GeneReview Scope
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
References
Chapter Notes
Authors:
Saroj Nimkarn
Prasanna K Gangishetti
Mabel Yau
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Available tests

66 tests are in the database for this condition.

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Clinical tests (66 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: CA21H, CAH1, CPS1, CYP21, CYP21B, P450c21B, CYP21A2
    Summary: cytochrome P450 family 21 subfamily A member 2

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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Reviews

Clinical resources

Practice guidelines

  • ACMG ACT Sheet, 2011
    American College of Medical Genetics ACT SHEET, Congenital Adrenal Hyperplasia, 2011
  • ACMG Algorithm, 2009
    American College of Medical Genetics Algorithm, Congenital Adrenal Hyperplasia, 2009
  • ACMG Algorithm, 2009
    American College of Medical Genetics and Genomics, Algorithm, Congenital Adrenal Hyperplasia (Elevated 17-OHP), 2009

Molecular resources

Consumer resources

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