Huntington Disease
Clinical Genetic Test
Help
offered by
GTR Test Accession: Help GTR000500316.3
CAP
INHERITED DISEASENERVOUS SYSTEM
Last updated in GTR: 2016-03-07
Last annual review date for the lab: 2023-02-08 Past due LinkOut
At a Glance
Diagnosis
Huntington disease
Genes (1): Help
HTT (4p16.3)
Molecular Genetics - Targeted variant analysis: Trinucleotide repeat by PCR or Southern Blot
This test confirms or rules out the diagnosis of HD …
Clinical specificity and sensitivity are >100% if family history is …
Establish or confirm diagnosis; Predictive risk information for patient and/or family members
Ordering Information
Offered by: Help
Genetics Laboratory
View lab's website
Test short name: Help
HD
Specimen Source: Help
Who can order: Help
  • Genetic Counselor
  • Health Care Provider
  • Licensed Physician
  • Nurse Practitioner
  • Physician Assistant
CPT codes: Help
**AMA CPT codes notice
Contact Policy: Help
Laboratory can only accept contact from health care providers. Patients/families are encouraged to discuss genetic testing options with their health care provider.
How to Order: Help
Samples should be submitted with the appropriate requisition form (DNA test request form). Samples are received Monday through Saturday. Blood should be collected in EDTA or ACD tubes.
Test service: Help
Clinical Testing/Confirmation of Mutations Identified Previously
Genetic counseling
Prenatal tesing
FISH Analysis
Drug Metabolism testing
Cytogenetics Analysis
Maternal Serum Screening
Uniparental Disomy (UPD) Testing
X-Chromosome Inactivation Studies
Test development: Help
Test developed by laboratory (no manufacturer test name)
Informed consent required: Help
No
Pre-test genetic counseling required: Help
Yes
Post-test genetic counseling required: Help
No
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
Methodology
Total methods: 1
Method Category Help
Test method Help
Instrument *
Targeted variant analysis
Trinucleotide repeat by PCR or Southern Blot
* Instrument: Not provided
Clinical Information
Test purpose: Help
Diagnosis
Clinical validity: Help
Clinical specificity and sensitivity are >100% if family history is notable and symptoms are typical of HTT.
View citations (1)
  • European Journal of Human Genetics (2014) 22, doi:10.1038/ejhg.2013.206
Clinical utility: Help
Establish or confirm diagnosis
View citations (1)
  • European Journal of Human Genetics (2014) 22, doi:10.1038/ejhg.2013.206

Predictive risk information for patient and/or family members
View citations (1)
  • European Journal of Human Genetics (2014) 22, doi:10.1038/ejhg.2013.206

Target population: Help
This test confirms or rules out the diagnosis of HD in a clinically symptomatic individual or an asymptomatic patient with a fmaily history. Symptoms of HD include chorea, discoordination of movement, depression, and memory loss.
View citations (1)
  • Technical standards and guidelines for Huntington disease testing. Potter NT, et al. Genet Med. 2004;6(1):61-5. doi:10.1097/01.gim.0000106165.74751.15. PMID: 14726813.
Recommended fields not provided:
Technical Information
Test Confirmation: Help
Positive results are confirmed by comparision with known positive controls
Availability: Help
Tests performed
Entire test performed in-house
Analytical Validity: Help
The CAG trinucleotide expansion in the HTT gene is present in almost all cases (98-99%) of HD and is absent in controls. Analytic sensitivity and specificity are estimated to be 99.5% and 99.2%, respectively.
View citations (2)
  • Palomaki GE, Richards CS. Assessing the analytic validity of molecular testing for Huntington disease using data from an external proficiency testing survey. Genet Med. 2012;14(1):69-75. doi:10.1038/gim.0b013e3182310bb5. Epub 2011 Sep 26. PMID: 22237433.
  • A worldwide study of the Huntington's disease mutation. The sensitivity and specificity of measuring CAG repeats. Kremer B, et al. N Engl J Med. 1994;330(20):1401-6. doi:10.1056/NEJM199405193302001. PMID: 8159192.
Proficiency testing (PT):
Is proficiency testing performed for this test? Help
Yes

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help
American College of Medical Genetics / College of American Pathologists, ACMG/CAP
Recommended fields not provided:
Regulatory Approval
FDA Review: Help
Category: FDA exercises enforcement discretion
Additional Information

IMPORTANT NOTE: NIH does not independently verify information submitted to GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.