26016 Huntington Disease, Molecular Analysis (HAD)

​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.

​Send specimen in original tube.  Specimen preferred to arrive within 96 hours of draw.

A recent clinical note is required. Testing cannot proceed without this information

For predictive testing, it is important to first document the presence of a CAG-repeat amplification in the HTT gene in an affected family member to confirm that molecular expansion is the underlying mechanism of disease in the family.

We strongly recommend that patients undergoing predictive testing receive genetic counseling both prior to testing and after results are available.

Predictive testing of an asymptomatic child is not recommended.

Test results should be interpreted in the context of clinical findings, family history, and other laboratory data. Errors in our interpretation of results may occur if information given is inaccurate or incomplete.

A previous bone marrow transplant from an allogenic donor will interfere with testing. Call Mayo Medical Laboratories at 800-533-1710 for instructions for testing patients who have received a bone marrow transplant.

​Huntington disease (HD) is an autosomal dominant progressive neurodegenerative disorder caused by a CAG repeat expansion in the HTT gene. HD is associated with cognitive impairment leading to dementia and a wide range of neuropsychiatric problems including apathy, depression, anxiety, and other behavioral disturbances. Additionally, affected individuals typically develop extrapyramidal symptoms (eg, dystonia, dysarthria, chorea, gait disturbance, postural instability, oculomotor dysfunction).

​An interpretive report will be provided.