New tools for the study of chromosome segregation and aneuploidy at the molecular level
The molecular mechanisms which allow the correct distribution of chromosomes during cell division are not yet well known. The centromere, because of its possible involvement in the attachment of sister chromatids and its participation in the formation of the kinetochore, may play an important role in these mechanisms. Trisomy 21 (Down syndrome, DS) provides a good model for studying aneuploidy resulting from the dysfunction of the chromosome distribution process. A possible means of analyzing the mechanisms leading to nondisjunction (NDJ) could be to determine the origin of the supernumerary chromosome 21 and to attempt to find some structural or physical characteristics of the potentially responsible centromere. This could be performed by using molecular tools which allow each of the two parental chromosomes 21 to be distinguished. Possible markers suitable for this purpose are DNA fragments that exhibit length polymorphisms.
KeywordsHydrolysis Recombination Agarose Electrophoresis Polyacrylamide
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