Ornithine Transcarbamylase Deficiency (OTC) Sequencing and Deletion/Duplication
Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Transport 3 mL whole blood. (Min: 2 mL)
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Background Information for Ornithine Transcarbamylase Deficiency (OTC) Sequencing and Deletion/Duplication:
Characteristics: Classic OTC deficiency is a urea cycle disorder characterized by hyperammonemia, cyclical vomiting, seizures, lethargy, coma and neonatal death if not treated. Clinical presentation varies widely in females, and some males can have non-classical forms.
Incidence: Approximately 1 in 20,000.
Penetrance: Variable depending on sex and mutation.
Cause: Pathogenic OTC gene mutations.
Clinical Sensitivity: Approaches 90 percent.
Methodology: Bidirectional sequencing of the entire coding region and intron-exon boundaries of the OTC gene. Multiplex ligation-dependent probe amplification (MLPA) to detect large OTC coding region deletions/duplications.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations and deep intronic mutations will not be detected. The breakpoints of large deletions/duplications will not be determined.
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
Laboratory Developed Test (LDT)
|Component Test Code*||Component Chart Name||LOINC|
|2004897||OTC Deficiency (OTC) Seq,DelDup Specimen||31208-2|
|2004898||OTC Deficiency (OTC) Seq,DelDup Interp||43233-6|
- OTC sequencing and deletion/duplication assay
- Urea Cycle Defect