U.S. flag

An official website of the United States government

GTR Home > Conditions/Phenotypes > Congenital hyperammonemia, type I

Congenital hyperammonemia, type I

Synonyms
CPS 1 deficiency; CPS I DEFICIENCY; Carbamoyl phosphate synthetase 1 deficiency; Carbamoyl phosphate synthetase I deficiency disease; Carbamoyl-phosphate synthase I deficiency; Carbamyl phosphate synthetase (CPS) deficiency; Hyperammonemia due to carbamoyl phosphate synthetase 1 deficiency
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

Carbamoyl phosphate synthetase I deficiency is an autosomal recessive inborn error of metabolism of the urea cycle which causes hyperammonemia. There are 2 main forms: a lethal neonatal type and a less severe, delayed-onset type (summary by Klaus et al., 2009). Urea cycle disorders are characterized by the triad of hyperammonemia, encephalopathy, and respiratory alkalosis. Five disorders involving different defects in the biosynthesis of the enzymes of the urea cycle have been described: ornithine transcarbamylase deficiency (311250), carbamyl phosphate synthetase deficiency, argininosuccinate synthetase deficiency, or citrullinemia (215700), argininosuccinate lyase deficiency (207900), and arginase deficiency (207800). [from OMIM]

Available tests

68 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Clinical tests (68 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: CPSASE1, GATD6, PHN, CPS1
    Summary: carbamoyl-phosphate synthase 1

Clinical features

Help
Imported from Human Phenotype Ontology (HPO)

Show allHide all

Reviews

Clinical resources

Practice guidelines

  • ACMG ACT, 2022
    American College of Medical Genetics and Genomics, Newborn Screening ACT Sheet, Decreased Citrulline, 2022
  • ACMG Algorithm, 2022
    American College of Medical Genetics and Genomics, Algorithm, Decreased Citrulline, 2022
  • ACMG ACT, 2012
    American College of Medical Genetics and Genomics, Transition to Adult Health Care ACT Sheet, Carbamoyl Phosphate Synthetase I (CPS I) Deficiency, 2012

Molecular resources

Consumer resources

IMPORTANT NOTE: NIH does not independently verify information submitted to the GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in the GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.