Tay-Sachs Disease (HEXA) Sequencing

Disorder Tay-Sachs Disease
Gene Name HEXA
Clinical info Tay-Sachs disease is an autosomal recessive lysosomal storage disorder caused by significantly reduced or absent activity of beta-hexosaminidase A. This deficiency results in accumulation of GM2 ganglioside which leads to the destruction of neurons in the brain and spinal cord. Although infants with Tay Sachs disease have normal developmental progress until the age of 3-6 months, regression becomes evident as the disorder progresses. Features of this condition include hypotonia, an increased startle reflex, inattentiveness, a retinal cherry-red spot, and loss of motor skills. Over time, seizures, hearing and vision loss, and spasticity develop, and most affected children die by the age of five. Tay Sachs disease occurs more frequently among specific groups including Ashkenazi Jewish, French Canadian, Pennsylvania Amish, and Louisiana Cajun populations.
Indications Molecular testing is useful to confirm the diagnosis and to identify the disease causing mutations within a family to allow for carrier testing and prenatal diagnosis.
Associated Tests Enzyme analysis for beta-hexosaminidase is available to rule out Tay-Sachs or Sandhoff disease. Sequencing of HEXA is also included in our NGS Lysosomal Storage Disease Panel.
Specimen Requirements 5 to 10 ml of peripheral blood collected in an EDTA (lavender top) Vacutainer tube is preferred. The minimal blood needed for reliable DNA isolation is 3 ml
Transport The specimen should be kept at room temperature and delivered via overnight shipping. FedEx is preferred. If shipment is delayed by one or two days, the specimen should be refrigerated and shipped at room temperature. Do not freeze the specimen. Samples collected on Friday can be safely designated for Monday delivery.
Turnaround time 21 days
Prenatal testing Prenatal diagnosis is available if the familial mutations are known. Additional fees for cell culture and maternal cell contamination may apply. Maternal cell contamination studies are required for all prenatal molecular tests. Contact the laboratory prior to sending a prenatal specimen.
CPT Codes Unknown mutation: 81406

Known mutation: 81403
Cost $1000 for sequencing

$350 for known mutation

Prenatal diagnosis for known mutation is $1000.  Please contact the laboratory for more information.

Contact For further information contact one of our This email address is being protected from spambots. You need JavaScript enabled to view it. at 1-800-473-9411.