#ExistInterpData>Background information for Tay-Sachs (HEXA) 7 Mutations, Fetal:
Characteristics: Lysosomal storage disease that in its severe form leads to loss of motor skills beginning at three to six months of age that progresses to blindness, seizures and total incapacitation and death by 4 years of age. A milder disease with later onset and slower progression is seen in affected adults. Adult-onset Tay-Sachs is associated with variable neurological findings including: progressive dystonia, spinocerebellar degeneration, motor neuron disease and bipolar form of psychosis.
Incidence: 1 in 3000 Ashkenazi Jewish individuals, unknown in other ethnicities.
Inheritance: Autosomal recessive.
Cause: Deleterious HEXA gene mutations.
Mutations Tested: Four severe (Delta7.6kb, IVS9(+1)G>A, 1278insTATC, IVS12(+1)G>C), one mild (G269S), and two pseudodeficiency alleles (R247W and R249W).
Clinical Sensitivity: 94 percent in Ashkenazi Jewish individuals, unknown in other ethnicities.
Methodology: PCR and allele specific primer extension by bead array with fluorescence detection.
Analytical sensitivity and specificity: Greater than 99 percent.
Limitations: HEXA mutations other than those specified above will not be detected. Rare diagnostic errors may occur due to primer site mutations.
For quality assurance purposes, ARUP Laboratories will confirm the above result at no charge following delivery. Order Confirmation of Fetal Testing and include a copy of the original fetal report (or the mother's name and date of birth) with the test submission. Please contact an ARUP genetic counselor at (800) 242-2787 extension 2141 prior to specimen submission.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.
See Compliance Statement C: www.aruplab.com/CS
||81255; Fetal Cell Contamination (FCC): 81265