groups with asthma. Thus the scientist must weigh the advantages of performing genetic studies in small, historically isolated populations with the potential disadvantage of being unable to eventually generalize the studies’ results. SEE ALSO Genetic Drift; Hardy-Weinberg Equilibrium; Inbreeding; Linkage and Recombination; Mapping; Population Bottleneck; Population Genetics; Tay-Sachs Disease.

BACKGROUND Tay-Sachs disease (TSD), or GM2 gangliosidosis, is a lethal autosomal recessive neurodegenerative disorder, which is caused by a deficiency of beta-hexosaminidase A (HEXA), resulting in lysosomal accumulation of GM2 ganglioside. The aim of this study was to identify the TSD-causing mutations in an Iranian population. METHODS In this study, we examined 31 patients for TSD-causing mu...

The results presented here provide the first single-cell genetic assay for Tay-Sachs disease based on real-time PCR. Individual lymphoblasts were lysed with an optimized lysis buffer and assayed using one pair of primers that amplifies both the wild type and 1278 + TATC Tay-Sachs alleles. The resulting amplicons were detected in real time with two molecular beacons each with a different colored...

A method for the preparation of highly purified @-hexosaminidase isozymes A and B from human placenta is presented. The purified enzymes possess identical molecular weight and exhibit similar kinetic parameters with artificial fluorogenic substrates. Both enzymes catalyze the hydrolysis of Tay-Sachs ganglioside (Cer-Glc-Gal(NeuAc)-GalNAc) and the corresponding asialo-derivative (Cer-Glc-GalGalN...

Tay-Sachs and Sandhoff diseases are lysosomal storage disorders that result from an inherited deficiency of beta-hexosaminidase A (alphabeta). Whereas the acute forms are associated with a total absence of hexosaminidase A and early death, the chronic adult forms exist with activity and protein levels of approximately 5%, and unaffected individuals have been found with only 10% of normal levels...

In an informal address to the 4th International Conference on Priorities in Health (Oslo, 23 September 2002), Professor Jeffrey Sachs - Chairperson of the WHO Commission on Macroeconomics and Health - maintained that the real causes of the inability of the world's poorest people to receive help for the lethal diseases that burden them did not include the "usual suspects" (corruption, mismanagem...

Recurrent anterior shoulder dislocation often leads to the presence of a Hill-Sachs lesion. A large Hill-Sachs lesion compromises shoulder stability and should be addressed with bone augmentation when it is too deep. Here, we introduce a method of arthroscopic bone grafting of the humeral head for the treatment of a deep Hill-Sachs lesion in patients with anterior shoulder instability. Our indi...