NameDown Syndrome [unknown gene(s)]
OrganismHomo sapiens
Aging PhenotypeShortened life-span
Allele TypeOverexpression
DescriptionPeople with Down syndrome develop the neuropathalogic lesions of Alzheimer disease significantly earlier than those without (Wisniewski et al, 1985) and have a shorter life span.
Gene FunctionKorenberg et al (1994) analyzed a panel of cell lines from people with Down syndrome caused by duplication of small regions of chromosome 21. Comparison of molecular breakpoints and detailed clinical evaluations led to a “phenotypic map” that was not consistent with a single region being responsible for most of the features of the syndrome (Korenberg et al, 1994).
Other PhenotypesThe major features of Down syndrome are mental retardation, characteristic facial features, congenital malformations of the heart and gastrointestinal tract, thyroid disease, and an increased incidence of leukemia (see, for example, Epstein, 1989). Neurons cultured in vivo from individuals with Down syndrome degenerate and show increased apoptosis (Busciglio and Yanker, 1995). Down syndrome neurons also show increased generation of reactive oxygen species and treatment with antioxidants can prevent degeneration.
Primary ReferenceWisniewski, K. E.; Wisniewski, H. M.; Wen, G. Y. (1985). Occurrence of neuropathological changes and dementia of Alzheimer's disease in Down's syndrome. Ann. Neurol. 17, 278-282. [Abstract]
Other ReferencesEpstein, C. J. Down syndrome, trisomy 21.In: Scriver, C. R.; Beaudet, A. L.; Sly, W. S.; Valle, D. Metabolic Basis of Inherited Disease. New York: McGraw-Hill (pub.) 1989. Pp. 291-326.
Korenberg, J. R.; Chen, X.-N.; Schipper, R.; Sun, Z.; Gonsky, R.; Gerwehr, S.; Carpenter, N.; Daumer, C.; Dignan, P.; Disteche, C.; Graham, J. M., Jr.; Hugdins, L.; McGillivray, B.; Miyazaki, K.; Ogasawara, N.; Park, J. P.; Pagon, R.; Pueschel, S.; Sack, [Abstract]
Busciglio, J., and Yankner, B. A. (1995). Apoptosis and increased generation of reactive oxygen species in Down's syndrome neurons in vitro. Nature 378, 776-9. [Abstract]
Relevant LinksOMIM:
KeywordsHomo, sapiens, human, cancer