Tay-Sachs Disease (TSD) is a fatal genetic disorder that has shown increased prevalence in the Ashkenazi Jewish population. If two unaffected parents each carry the recessive TSD gene, they have a 1-in-4 chance of bearing an affected TSD child. Some couples will proactively get tested for the recessive TSD gene, to see if they are at risk of bearing a child with TSD.
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