Diseases Tay-Sachs

Taylor system Tay-Sachs disease Tazettine [507-79-9] Tazicef Tazidime... 

GM2 gangliosidosis (also known as Tay-Sachs disease) is a rare disorder caused by mutations in the gene encoding the lysosomal, heterodimeric ss-hexosaminidase... 

Tay-Sachs disease Hexosaminidase A Cer—Gic—Gal(NeuAc)-i-GalNAc GM2Gangiioside Mental retardation, blindness, muscular weakness. 

Sandhoff s disease is due to a deficiency of the HexB gene. Clinical features are similar to those of Tay-Sachs disease. Late infantile, juvenile and adults variants have also been described. 

Patients with sialidosis show a striking syndrome characterized by action myoclonus, cerebellar ataxia and a macular cherry red spot similar to that in Tay-Sachs disease but with preserved intellect. 

In contrast, the Tay-Sachs disease test patented by the Department of Health and Human Services costs about 100 per test, and the screening test for two breast cancer genes patented by a biotechnology firm costs 2,400 per test (Krimsky, 1999). 

It is also important to understand the source and significance of genetic variations. The Pima Indians have the highest rates of diabetes in the world Tay-Sachs disease is primarily found in Ashkenazi Jews. Contemporary literature indicates that these differences stem from reproductive isolation, not race. Genetic traits common to persons with sickle-cell disease are related to malaria frequency and not our social view of race. This is why the disease can be found in high frequency in Yemen, West Africa, Greece, and Saudi Arabia. 

Racial and ethnic groups may also vary in the extent to which they are carriers of autosomal recessive or dominant diseases that could be inherited by offspring. African Americans will be subject to many of the same diseases as whites, for example, cystic fibrosis, but the incidence of the disease may vary. In some cases, however, the incidence of disease may be higher among African Americans, just as it is for some white subgroups, for example, the higher incidence of Tay-Sachs disease and BRCA1 and -2 mutations in Ashkenazi Jews. 

Tay-Sachs disease, 76, 279 testing associated with, 195-196, 307 Technological change, policy implications of, 236-237... 

Examples of genetic conditions that are more common in particular ethnic groups are sickle cell anemia, which is more common in people of African, African-American, or Mediterranean heritage and Tay-Sachs disease, which is more likely to occur among people of Ashkenazi (eastern and central European) Jewish or French Canadian ancestry. It is important to note, however, that these disorders can occur in any ethnic group. 

A 30-year-old man is phenotypically normal, but two of his siblings died from infantile Tay-Sachs disease, an autosomal recessive condition that is lethal by the age of five. What is the risk that this man is a heterozygous carrier of the disease-causing mutation ... 

Individuals with a family history of an autosomal or X-linked recessive disease may wish to know whether they are a heterozygous carrier of the disease. This can be established by genetic diagnosis (e.g., for cystic fibrosis, hemochromatosis, PKU, or albinism). In some specific cases, a population at high risk for a specific disease may be screened for carrier status using genetic diagnosis (e.g., Tay-Sachs disease in the Jewish population [see Clinical Correlate]). 

A-acetyl-)3-D-hexosaminides. The enzyme can also utilize A-acetylglucosides and A-acetylgalactosides as substrates. The associated human genetic disorders are known as Sandhoff s disease and Tay-Sachs disease. 

The biochemical defect In Tay-Sachs disease is an inherited deficiency of -hexosaminidase, a lysosomal enzyme responsible for hydrolysis ofGM2 ganglioside, which accumulates abnormally in the lyso-somes. 

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