*If prior authorization is not submitted, test may be delayed.
Test Overview
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.
Analysis for the presence of UBE3A mutations in patients with a phenotype consistent with Angelman Syndrome. The diagnosis of AS rests on a combination of clinical features and molecular genetic testing and/or cytogenetic analysis. Analysis of parent-specific DNA methylation imprints in the 15q11.2-q13 chromosome region detects approximately 78% of individuals with AS, including those with a deletion, uniparental disomy (UPD), or an imprinting defect (ID). Less than 1% of individuals with AS have a cytogenetically visible chromosome rearrangement (translocation or inversion). UBE3A sequence analysis detects mutations in approximately 11% of individuals with AS. Methylation analysis and UBE3A sequence analysis identifies genetic alterations in approximately 90% of individuals with AS. The remaining 10% of individuals with classic phenotypic features of AS have the disorder as a result of an as-yet unidentified genetic mechanism.
Interpretive report provided.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
This assay will not detect large deletions in the UBE3A gene or intronic mutations outside the region sequenced in the UBE3A gene.
Test Details
21 - 28 days
- UBE3AS
- UBE3A Gene Sequencing
- UBE3ASS
- UBE3A Sequencing Shadow
- Ubiquitin Protein Ligase E3A Gene Sequencing
- Angelman Syndrome
- Autism / Intellectual Disability
Specimen Requirements
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.
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.