Panel Description
Diseases Targeted:
Transthyretin-Related Hereditary Amyloidosis
Overview:
The Transthyretin-Related Hereditary Amyloidosis Test examines 1 gene associated with transthyretin-related hereditary amyloidosis (TTR).Who is this test for?
Patients with a personal and/or family history suggestive of TTR. Red flags for TTR can include, but are not limited to, muscle weakness and numbness, central nervous system issues, buildup of amyloid proteins within the body, particularly the brain and spinal cord, enlarged heart, and gastrointestinal problems.What are the potential benefits for my patient?
Patients identified with TTR can benefit from increased surveillance and preventative steps to better manage their risks. Medical intervention can include medications, supportive care to help manage symptoms, and liver transplantation. 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.Test Description
Order Options:
Turnaround Time:
2.9 – 3.857142857142857 weeks
Cost:
Call for details
Genes:
TTR
( 1 gene )
Coverage:
99.9% at 20x
Specimen Requirements:
Blood (two 4ml EDTA tubes, lavender top) or Extracted DNA (3ug in EB buffer) or Buccal Swab or Saliva (kits available upon request)
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.
Resource
– Sekijima, Y,, Yoshida, K., Tokuda, T., et al. Familial Transthyretin Amyloidosis. 2001 Nov 5 [Updated 2012 Jan 26]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; (1993-2017)
Appendix
This is a next generation sequencing (NGS) test appropriate for individuals with clinical signs and symptoms, suspicion of, or family history of Transthyretin Amyloidosis. Sequence variants and/or copy number variants (deletions/duplications) within the TTR gene will be detected with >99% sensitivity. Variants classified as unknown significance (VUS), likely pathogenic, or pathogenic will be reported. Benign and likely benign variants are generally not reported. Reflex to clinical exome (“All-in-One”) and whole exome (“Whole-in-One”) is available by request.