The genetic basis of amaurotic family idiocy

Studies of Red-Cell Stromal Lipids in Tay-Sachs Disease and Other Lipidoses*

“…Extensive family studies (10,11) have shown that this disease is inherited as an autosomal recessive trait with complete penetrance. Hence the parents must be heterozygous carriers and might be expected to show some abnormality by analogy with the situation in phenylketonuria (30).…”

Multimedia messages in genetics: Design, development, and evaluation of a computer-based instructional resource for secondary school students in a Tay Sachs disease carrier screening program

“…Tay Sachs disease (TSD) is a neurodegenerative disorder, fatal in children usually by the age of five, with an autosomal recessive pattern of inheritance. 1 The identification of the enzymatic deficiency 2 of hexosaminidase A in those affected with TSD enabled the worldwide implementation of carrier screening programs within the high risk Ashkenazi Jewish community. 3,4 In Australia, the Melbourne TSD carrier screening program involves senior secondary school students and has been offered successfully since 1997.…”

Hardy-Weinberg Equilibrium as Foundational

“…He notes: "Slome's (1933) analysis of published sibships clearly indicates that it is due to a single autosomal gene in spite of a slight excess of female cases." [11] Since then extensive research has mapped the relevant HEXA gene to chromosome 15. O'Brien writes: "The widespread absence of hexosaminidase A in the tissues, the normal or increased activity of other lysosomal hydrolases, the normal or increased activity of hexosaminidase A in other gangliosidoses, and the partial reduction of this enzyme in the serum of individuals heterozygous for the Tay-Sachs gene, suggest that the absence of hexosaminidase A is the fundamental enzymic defect in Tay-Sachs disease."…”

“…Note that the gene frequency is 1 60 and the population is in Hardy-Weinberg form in both (11) and (12). Neither model is fully valid in that children with Tay-Sachs die long before reproductive age.…”