Test Overview
Test Methodology

The coding exons and associated, adjacent consensus splice sites of the OTC gene are amplified using specific primers, and bidirectionally sequenced using a fluorescent method.

Test Usage

This test is used to detect the presence of OTC mutations in patients with Ornithine Transcarbamylase Deficiency or for carrier testing in families with a known OTC mutation.

Reference Range *

Interpretive report provided.

Test Limitations

This assay will not detect large deletions in the OTC gene or intronic mutations outside the region sequenced in the OTC gene.

Test Details
Days Set Up
Monday - Friday
Analytic Time

21 - 28 days

Soft Order Code
MiChart Code
OTC (Ornithine Transcarbamylase Deficiency) Gene Sequencing
  • OTC Gene Sequencing Shadow
  • OTCS
  • OTC Gene Sequencing
  • OTC Deficiency
  • Valproate Sensitivity
  • Valproic Acid Sensitivity
MMGL Molecular Genetics
Specimen Requirements
Collection Instructions

Collect specimen in a lavender top tube. Send intact specimen within 24 hours if stored at room temperature or within 5 days if stored refrigerated. Include the patient's family history, pedigree, and ethnicity on the test requisition. Obtaining informed consent from the patient prior to genetic testing is strongly recommended. If desired, a UMHS Request and Consent for Genetic Testing form can be obtained from the MMGL Molecular Genetics Laboratory by contacting the MLabs Client Services Center at 800-862-7284 or online at https://mlabs.umich.edu/sites/default/files/2020-01/file/pci-mmgl_infor….

Normal Volume
5 - 10 mL EDTA whole blood
Minimum Volume
2 mL EDTA whole blood
Additional Information

By ordering this test the clinician acknowledges that informed consent has been obtained from the patient as required by applicable state or federal laws and the ordering clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. Test includes medical geneticist interpretation of results billed as a separate additional charge. This test is not available without interpretation.

CPT Code
Fee Code
Pro Fee CPT
NY State Approved