Test Overview
Test Methodology

Polymerase Chain Reaction

Test Usage

Molecular confirmation of clinically suspected cases of Huntington disease (HD). Presymptomatic testing for individuals with a family history of HD and a documented expansion in the HTT gene

Reference Range *

Normal alleles: <27 CAG repeats
Intermediate alleles: 27-35 CAG repeats
Reduced penetrance: 36-39 CAG repeats
Full penetrance: >39 CAG repeats
An interpretive report will be provided.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details
Days Set Up
Wednesday
Analytic Time

8 - 12 days

Soft Order Code
HAD
Synonyms
    Laboratory
    Sendout
    Reference Laboratory
    Mayo HAD
    Section
    Special Testing
    Specimen Requirements
    Collection Instructions

    Collect specimen in lavender or yellow top tube. Invert several times to mix. Send to Specimen Processing at ambient temperature. Specimen preferred to arrive at Mayo within 96 hours of collection.

    Special Handling

    Specimen preferred to arrive at Mayo within 96 hours of collection.

    Alternate Specimen
    Any anticoagulant is acceptable
    Normal Volume
    3 mL whole blood
    Minimum Volume
    1 mL whole blood
    Storage Temperature
    Ambient preferred, frozen or refrigerated acceptable. Specimen preferred to arrive at Mayo within 96 hours of collection
    Additional Information

    Test performed by Mayo Clinic Laboratories

    Billing
    CPT Code
    81271
    NY State Approved
    No