Huntington Disease (HTT) Genetic Testing (Repeat Expansion)

CPT: 81271

Special Instructions

This assay is not currently available in New York state.

A complete Informed Consent should accompany specimens. See “Related Documents” to download.

Expected Turnaround Time

12 - 14 days

Related Documents

For more information, please view the literature below.

Huntington Disease Informed Consent

    Specimen Requirements


    Whole blood


    4 mL


    Lavender-top (EDTA) tube

    Storage Instructions

    Ship at room temperature overnight, but stable up to 5 days post-collection at room temperature. Do not freeze.

    Causes for Rejection

    Frozen blood EDTA tube

    Test Details


    Huntington disease (HD) is a neurodegenerative disease of mid-life onset that produces choreic movements and cognitive decline, often accompanied by psychiatric changes. The disease is caused by an expansion of the CAG repeats in 3-5 out of 100,000 individuals. However, the prevalence of HD exceeds 15 per 100,000 in some populations, mostly of Western European origin. Juvenile-onset HD occurs in approximately 5% of affected patients, is rapidly progressive, and presents with rigidity, spasticity, and intellectual decline before the age of 20 years. The symptoms result from the selective loss of neurons, most notably in the caudate nucleus and putamen, and there is currently no effective treatment.


    Maximum reportable sizing: 150 repeats.

    This test was developed and its performance characteristics determined by LabCorp. It has not been cleared or approved by the Food and Drug Administration.


    Repeat-Primed PCR (QP-PCR)

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