Tay-Sachs: HexA gene sequencing
GTR Test Accession: Help GTR000556581.1
Last updated in GTR: 2017-08-16
Last annual review date for the lab: 2023-10-05 LinkOut
At a Glance
Tay-Sachs disease
Genes (1): Help
HEXA (15q23)
Molecular Genetics - Mutation scanning of the entire coding region: Bi-directional Sanger Sequence Analysis
Not provided
Establish or confirm diagnosis
Ordering Information
Offered by: Help
Test short name: Help
HexA gene sequencing
Specimen Source: Help
  • Amniocytes
  • Amniotic fluid
  • Bone marrow
  • Cell culture
  • Chorionic villi
  • Cord blood
  • Fetal blood
  • Fibroblasts
  • Fresh tissue
  • Isolated DNA
  • Peripheral (whole) blood
  • Product of conception (POC)
  • View specimen requirements
Who can order: Help
  • Genetic Counselor
  • Health Care Provider
  • In-State Patients
  • Licensed Physician
  • Out-of-State Patients
  • Physician Assistant
  • Public Health Mandate
Contact Policy: Help
Post-test email/phone consultation regarding genetic test results and interpretation is provided to patients/families.
Pre-test email/phone consultation regarding genetic test results and interpretation is provided to patients/families.
How to Order: Help
Kindly contact us for a prior collection of any specimen or you can visit our website.
Order URL
Test service: Help
Genetic counseling
Result interpretation
Test additional service: Help
Custom Prenatal Testing
Custom mutation-specific/Carrier testing
Test development: Help
Test developed by laboratory (no manufacturer test name)
Informed consent required: Help
Based on applicable state law
Pre-test genetic counseling required: Help
Post-test genetic counseling required: Help
Recommended fields not provided:
Conditions Help
Total conditions: 1
Condition/Phenotype Identifier
Test Targets
Genes Help
Total genes: 1
Gene Associated Condition Germline or Somatic Allele (Lab-provided) Variant in NCBI
Total methods: 1
Method Category Help
Test method Help
Mutation scanning of the entire coding region
Bi-directional Sanger Sequence Analysis
Automated sequencer
Clinical Information
Test purpose: Help
Clinical utility: Help
Establish or confirm diagnosis

Target population: Help
View citations (1)
  • Mistri M, Tamhankar PM, Sheth F, Sanghavi D, Kondurkar P, Patil S, Idicula-Thomas S, Gupta S, Sheth J. Identification of novel mutations in HEXA gene in children affected with Tay Sachs disease from India. PLoS One. 2012;7(6):e39122. doi:10.1371/journal.pone.0039122. Epub 2012 Jun 18. PMID: 22723944.
Variant Interpretation:
What is the protocol for interpreting a variation as a VUS? Help
For interpreting variant as VUS we use 1000 Genome Database, Human Genome mutation database (HGMD), ExAC database, we also check minor/major allele frequency. Furthermore, we use various softwares to identify the pathogenicity of VUS.All VUS are reconfirmed by Sanger sequencing. All variants are submitted to clinvar.

Are family members with defined clinical status recruited to assess significance of VUS without charge? Help

Will the lab re-contact the ordering physician if variant interpretation changes? Help
Yes. The normal process is we reevaluate VUS data from time to time and whenever find some changes we generate new report, and dispatch the same to patient and also inform the referring physician. Usually it is not the person who is investigated at the lab need to recontact but lab … View more
Recommended fields not provided:
Technical Information
Availability: Help
Tests performed
Interpretation performed in-house
Report generated in-house
Specimen preparation performed in-house
Wet lab work performed in-house
Analytical Validity: Help
The sanger sequencing is greater than 99% sensitive for detecting common variants
Proficiency testing (PT):
Is proficiency testing performed for this test? Help

Method used for proficiency testing: Help
Software used to interpret novel variations Help
SIFT, Polyphen, Mutation Taster etc.

Laboratory's policy on reporting novel variations Help
After confirming VUS by Sanger sequencing, we screen other family members for confirming its pathogenicity and dispatch report to patients and also communicate report to the referring doctors by special telephonic talk and email.
Recommended fields not provided:
Regulatory Approval
FDA Review: Help
Category: Not Applicable
Additional Information

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