There two types of carrier screening tests: DNA and biochemical. Tay-Sachs and Sandhoff carrier screening is available through DNA or biochemical testing. A combination of both DNA and biochemical are recommended for the most accurate results.
DNA carrier screening detects specific known mutations that are ‘looked’ for in the test. A negative DNA carrier result does not eliminate your chances of being a carrier because of the possibility you carry an unknown
mutation or one not ‘looked’ for in the test.
Biochemical testing is also called
enzyme assay. It detects the level of
enzyme in the blood. Enzyme assay can be done using serum or leukocyte.
Serum is the standard test but leukocyte is recommended when the person being tested is pregnant, on birth control pills or taking any medications that affect hormones because all of these situations can potentially interfere with the accuracy of the serum test.
NOTE: A combination of DNA and biochemical testing is recommended for Tay-Sachs screening for the most sensitive and accurate results. View the NTSAD Position Statement on Tay-Sachs Screening (.doc)
