Short QT Syndrome

$600.00

Category:

About the Test

The Short QT Syndrome Panel examines 6 genes associated with hereditary Short QT syndrome (SQTS).

Overview

The Short QT Syndrome Panel examines 6 genes associated with hereditary Short QT syndrome (SQTS).

Genes

 6 Genes

CACNA1C, CACNA2D1, CACNB2, KCNH2, KCNJ2, KCNQ1

Disorders
Gene Function
Who Is This Test For?

Patients with a personal and/or family history suggestive of SQTS. Short QT syndrome is defined by a shortened QT interval on an electrocardiogram (ECG). Red flags for SQTS can include, but are not limited to, atrial fibrillation, ventricular tachycardia, ventricular fibrillation, syncope, cardiac arrest, or sudden cardiac death. SQTS is very rare.

Potential Benefits To My Patients

Patients identified with SQTS can benefit from increased surveillance and preventative steps to better manage their risks. Medical intervention can include beta blockers, implantable devices, and lifestyle changes. Also, your patient’s family members can be tested to help define their risk. If a pathogenic variant is identified in your patient, close relatives (children, siblings, parents) could have as high as a 50% risk to also be at increased risk. In some cases, screening should begin in childhood.

Clinical Utility
Lab Method & Assay
  • Next-Generation  Sequencing
  • Deletion/Duplication Analysis
  • Pathogenic and Likely Pathogenic Variants Confirmed With Sanger Sequencing
  • Coverage: 96% at 20X
Test Limitations

All sequencing technologies have limitations. This analysis is performed by Next Generation Sequencing (NGS) and is designed to examine coding regions and splicing junctions. Although next generation sequencing technologies and our bioinformatics analysis significantly reduce the contribution of pseudogene sequences or other highly-homologous sequences, these may still occasionally interfere with the technical ability of the assay to identify pathogenic variant alleles in both sequencing and deletion/duplication analyses. Sanger sequencing is used to confirm variants with low quality scores and to meet coverage standards. If ordered, deletion/duplication analysis can identify alterations of genomic regions which include one whole gene (buccal swab specimens and whole blood specimens) and are two or more contiguous exons in size (whole blood specimens only); single exon deletions or duplications may occasionally be identified, but are not routinely detected by this test. Identified putative deletions or duplications are confirmed by an orthogonal method (qPCR or MLPA). This assay will not detect certain types of genomic alterations which may cause disease such as, but not limited to, translocations or inversions, repeat expansions (eg. trinucleotides or hexanucleotides), alterations in most regulatory regions (promoter regions) or deep intronic regions (greater than 20bp from an exon). This assay is not designed or validated for the detection of somatic mosaicism or somatic mutations.

Gene Specifics
Test Code
Specimen Requirements

Buccal Swab

Turn Around Time

3 – 5 weeks

CPT Codes

81403, 81406, 81479

NOTE: The CPT codes listed on the website are in accordance with Current Procedural Terminology, a publication of the American Medical Association. CPT codes are provided here for the convenience of our clients. Clients who bill for services should make the final decision on which codes to use.

References
  1. Beckmann, B.M., Pfeufer, A., & Kääb, S. Inherited cardiac arrhythmias: diagnosis, treatment, and prevention. Dtsch Arztebl Int. 2011 Sep;108(37):623-33 (2011)
  2. Brugada, R., Hong, K., Cordeiro, J.M., Dumaine, R. CMAJ. Short QT syndrome. Nov 22;173(11):1349-54. (2005)
  3. Kim, J.B. Channelopathies. Korean J Pediatr. 2014 Jan;57(1):1-18. doi: 10.3345/kjp.2014.57.1.1. (2014)