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HelpTest Code LQTSG Long QT Syndrome Gene Panel, Varies
Ordering Guidance
This test is intended for genetic screening for and diagnosis of long QT syndrome.
For Brugada syndrome genetic testing, order SCN5A / Brugada Syndrome Multi-Gene Panel, Blood.
For comprehensive inherited cardiac arrhythmia genetic testing, order CARGG / Comprehensive Arrhythmia Gene Panel, Varies.
Customization of this panel and single gene analysis for any gene present on this panel are available. For more information see CGPH / Custom Gene Panel, Hereditary, Next-Generation Sequencing, Varies.
Targeted testing for familial variants (also called site-specific or known mutations testing) is available for the genes on this panel. See FMTT / Familial Variant, Targeted Testing, Varies. To obtain more information about this testing option, call 800-533-1710.
Shipping Instructions
Specimen preferred to arrive within 96 hours of collection.
Necessary Information
Prior Authorization is available, but not required, for this test. If proceeding with the prior authorization process, submit the required form with the specimen.
Specimen Required
Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. Call 800-533-1710 for instructions for testing patients who have received a bone marrow transplant.
Specimen Type: Whole blood
Container/Tube:
Preferred: Lavender top (EDTA) or yellow top (ACD)
Acceptable: Any anticoagulant
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix blood
2. Send whole blood specimen in original tube. Do not aliquot.
Specimen Stability Information: Ambient (preferred)/Refrigerated
Forms
. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available:
-Informed Consent for Genetic Testing (T576)
-Informed Consent for Genetic Testing (Spanish) (T826)
2. Hereditary Cardiomyopathies and Arrhythmias Patient Information
3. Long QT Syndrome Gene Panel (LQTSG) Prior Authorization Ordering Instructions
4. If not ordering electronically, complete, print, and send a Cardiovascular Test Request Form (T724) with the specimen.
Useful For
Providing a genetic evaluation for patients with a personal or family history suggestive of long QT syndrome (LQTS)
Establishing a diagnosis of LQTS
Method Name
Sequence Capture and Targeted Next-Generation Sequencing followed by Polymerase Chain Reaction (PCR) and Sanger Sequencing.
Reporting Name
Long QT Syndrome Gene PanelSpecimen Type
VariesSpecimen Minimum Volume
1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Varies | ||
Reference Values
An interpretive report will be provided.
Interpretation
All detected variants are evaluated according to American College of Medical Genetics and Genomics recommendations.(5) Variants are classified based on known, predicted, or possible pathogenicity and reported with interpretive comments detailing their potential or known significance.
Clinical Reference
1. Alders M, Bikker H, Christiaans I: Long QT syndrome. In: Adam MP, Ardinger HH, Pagon RA, et al, eds. GeneReviews [Internet]. University of Washington, Seattle; 2003 . Updated February 8, 2018. Accessed July 27, 2022. Available at www.ncbi.nlm.nih.gov/books/NBK1129/
2. Giudicessi JR, Ackerman MJ: Genetic testing in heritable cardiac arrhythmia syndromes: differentiating pathogenic mutations from background genetic noise. Curr Opin Cardiol. 2013 Jan;28(1):63-71. doi:10.1097/HCO.0b013e32835b0a41
3. Veerapandiyan A, Statland JM, Tawil R: Andersen-Tawil syndrome. In: Adam MP, Ardinger HH, Pagon RA, et al, eds. GeneReviews [Internet]. University of Washington, Seattle; 2004. Updated June 7, 2018. Accessed July 27, 2022. Available at www.ncbi.nlm.nih.gov/books/NBK1264/
4. Napolitano C, Timothy KW, Bloise R, Priori SG: CACNA1C-related disorders. In: Adam MP, Ardinger HH, Pagon RA, et al, eds. GeneReviews [Internet]. University of Washington, Seattle; 2006. Updated February 11, 2021. Accessed July 27, 2022. Available at www.ncbi.nlm.nih.gov/books/NBK1403/
5. Richards S, Aziz N, Bale S, et al: Standards and guidelines for the interpretation of sequence variants: a joint consensus recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. Genet Med. 2015 May;17(5):405-424
Day(s) Performed
Varies
Report Available
28 to 42 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
81403
81406 x2
81407
81479
81479 (if appropriate for government payers)
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| LQTSG | Long QT Syndrome Gene Panel | 55146-5 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 617352 | Test Description | 62364-5 |
| 617353 | Specimen | 31208-2 |
| 617354 | Source | 31208-2 |
| 617355 | Result Summary | 50397-9 |
| 617356 | Result | 82939-0 |
| 617357 | Interpretation | 69047-9 |
| 617358 | Additional Results | 82939-0 |
| 617359 | Resources | 99622-3 |
| 617360 | Additional Information | 48767-8 |
| 617361 | Method | 85069-3 |
| 617362 | Genes Analyzed | 48018-6 |
| 617363 | Disclaimer | 62364-5 |
| 617364 | Released By | 18771-6 |