Tay-Sachs disease occurs at an increased frequency in individuals of Ashkenazi Jewish and French-Canadian descent. It is a lysosomal storage disorder that results in untreatable neurological degeneration and, in the common infantile form, death by 5 years of age.
Couples who are planning a pregnancy or who are already pregnant may decide to have testing to find out if they are carriers and at risk of having a baby with Tay-Sachs disease. It is standard of care to offer carrier screening to individuals of Ashkenazi Jewish descent for Bloom syndrome, Canavan disease, cystic fibrosis, familial dysautonomia, Fanconi anemia group C, Gaucher disease, mucolipidosis type IV, Niemann-Pick disease type A and Tay-Sachs disease. If both parents are found to be carriers, prenatal diagnosis by CVS or amniocentesis is available. Our Tay-Sachs disease mutation analysis tests for 8 mutations (6 disease-causing mutations and 2 pseudodeficiency alleles). We perform Tay-Sachs enzyme analysis (hexosaminidase A) in conjunction with Tay-Sachs mutation analysis to provide a carrier detection rate of 97-98% in the Ashkenazi Jewish population.
CPT Codes:
83893(3), 83894(1), 83896(9), 83900(1), 83901(2)
Specimen Requirements:
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Blood:
- Please Note: Tay-Sachs DNA testing should be performed only as an adjunct to enzymatic testing. If an individual has previously had enzymatic testing, please provide results. If ordering multiple tests, send 30 cc whole blood. If sending blood for both DNA and enzyme testing, send two tubes.
- Adult: 20 ml whole blood in ACD-A (yellow-top) or EDTA (lavender-top) tube.
- Turnaround Time:
10-14 days
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Prenatal:
- Please Note: Call a laboratory genetic coordinator prior to obtaining any prenatal specimens. Prenatal DNA testing is recommended only for carrier couples with identified mutations.
All prenatal specimens (including cord blood) must be accompanied by a maternal blood or mouthwash specimen for analysis of possible maternal cell contamination.
- Discard first 2 ml; then 10 ml amniotic fluid in 15 ml orange-top polypropylene tube, 10-15 mg chorionic villi in laboratory-provided screw-top tubes with sterile transport medium or one T-25 flask of confluent fetal cells.
- Additional specimen must be obtained for back-up culture at one of our cytogenetics laboratories or another facility.
- If additional testing is desired, more amniotic fluid is needed. For example, chromosome analysis requires an additional 15-25 ml (see Cytogenetics – Amniotic Fluid Chromosome Analysis test page) and AFAFP requires an additional 2 ml (see Amniotic Fluid Alpha-Fetoprotein - AFAFP test page).
- Turnaround Time:
10-14 days(when cell culture required, add ~2 weeks)
Client Services:
Reproductive/Genetics
800-848-4436
Specimen Services/Pickup:
877-246-1226