ClinGen Dosage Sensitivity Curation Page

See New Dosage Map New! The ClinGen Dosage Sensitivity curations and downloads that are available at this site are now also available at www.clinicalgenome.org. Click on the button to access Dosage Sensitivity in the context of ClinGen's other curated information, including Gene-Disease Validity and Clinical Actionability.

OTC

  • Curation Status: Complete

Location Information

Select assembly: (NC_000023.10) (NC_000023.11)

Haploinsufficiency phenotype comments:

Loss of function mutations result in OTC deficiency, a common type of urea cycle disorder. Males are always affected and 15% of carrier females will have hyperammonemia at some point in their lifetimes and may have cognitive symptoms even in the absence of hyperammonemia. See GeneReviews for Urea Cycle Disorders.

The loss-of-function and triplosensitivity ratings for genes on the X chromosome are made in the context of a male genome to account for the effects of hemizygous duplications or nullizygous deletions. In contrast, disruption of some genes on the X chromosome causes male lethality and the ratings of dosage sensitivity instead take into account the phenotype in female individuals. Factors that may affect the severity of phenotypes associated with X-linked disorders include the presence of variable copies of the X chromosome (i.e. 47,XXY or 45,X) and skewed X-inactivation in females.

  • Triplosensitivity score: 0
  • Strength of Evidence (disclaimer): No evidence for dosage pathogenicity

Triplosensitivity phenotype comment:

There have been no reports of focal duplications of OTC.

The loss-of-function and triplosensitivity ratings for genes on the X chromosome are made in the context of a male genome to account for the effects of hemizygous duplications or nullizygous deletions. In contrast, disruption of some genes on the X chromosome causes male lethality and the ratings of dosage sensitivity instead take into account the phenotype in female individuals. Factors that may affect the severity of phenotypes associated with X-linked disorders include the presence of variable copies of the X chromosome (i.e. 47,XXY or 45,X) and skewed X-inactivation in females.