title: Estimation of the frequency of hexosaminidase a variant alleles in the American Jewish population.
abstract: There appear to be several alleles of the hexosaminidase A (HEX A) gene that lead to different clinical syndromes. In addition to the infantile-onset Tay-Sachs disease (TSD), there is a juvenile-onset and an adult-onset form, which are also characterized by low HEX A levels. There are also apparently healthy adults with low HEX A activity. Based primarily on data from population screening for TSD carrier status, we estimate the allele frequency of the combined variant alleles for which data are available to be about 4.5 x 10(-4) and the frequency of adults showing zero HEX A levels (when tested using artificial substrate) to be about 1:67,000. The implications for population screening and prenatal diagnosis are discussed.
mesh_terms: D000328:Adult; D000483:Alleles; D005260:Female; D005787:Gene Frequency; D006580:Genetic Carrier Screening; D005820:Genetic Testing; D014644:Genetic Variation; D054818:Hexosaminidase A; D006596:Hexosaminidases / Q000235:genetics*; D006801:Humans; D007585:Jews; D008297:Male; D010641:Phenotype; D013661:Tay-Sachs Disease / Q000517:prevention & control*; D014481:United States; D001619:beta-N-Acetylhexosaminidases
chemical_list: D006596:Hexosaminidases; D054818:Hexosaminidase A; D001619:beta-N-Acetylhexosaminidases