Test Overview
Test Methodology

All coding exons (plus 15 bp upstream and downstream of each coding exon) of the targeted gene(s) are captured, sequenced using NGS and aligned to the human reference genome. A minimum NGS coverage of 20X is achieved for all coding exons +/- 5 bp, and a minimum coverage of 10X an additional 10 bp from +/- 6 bp through +/- 15 bp. A minimum coverage of 10X is achieved for all clinically significant promoter regions. Regions which do not meet these coverage metrics are filled with targeted Sanger Sequencing. Variants in the targeted regions that are of potential clinical significance, based on the ACMG guidelines for interpretation of sequence variants (PMID: 25741868), will be reported. All reported variants of potential clinical significance not meeting the sequencing quality criteria will be confirmed by a different technology.

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.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

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
OTCS
MiChart Code
OTC (Ornithine Transcarbamylase Deficiency) Gene Sequencing
Synonyms
  • OTCSS
  • OTC Gene Sequencing Shadow
  • OTCS
  • OTC Gene Sequencing
  • OTC Deficiency
  • Valproate Sensitivity
  • Valproic Acid Sensitivity
Laboratory
MMGL
Section
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/media/188.

Normal Volume
1-5 mL EDTA whole blood
Minimum Volume
1 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.

Billing
CPT Code
81405
Fee Code
DA023
Pro Fee CPT
G0452-26