These animals provide a unique system for studying the consequences of increased dosage of the Cu/Zn-superoxide dismutase gene in Down syndrome and the role of this enzyme in a variety of other pathological processes.
Because a small region of chromosome 21 containing the ets-2 gene is duplicated in patients with Alzheimer's disease, as well as in karyotypically normal Down syndrome, duplication of a subsection of the critical segment of chromosome 21 that is duplicated in Down syndrome may be the genetic defect in Alzheimer's disease.
The erythrocyte superoxide dismutase-1 (SOD-1) was found to be normal, and so we conclude that SOD-1 excess is not necessarily observed in patients with Down's syndrome caused by partial 21 trisomy.
These data are consistent with the possibility that gene dosage of superoxide dismutase 1 contributes to oxygen metabolism modifications previously described in Down's syndrome.
Molecular genetic analysis of Down syndrome (DS) patients with partial trisomy 21 allowed us to reinforce the supposition that ETS2 may be a gene of the minimal DS genetic region.
Here we show, by using a somatic-cell/hybrid-cell mapping panel, in situ hybridization, and transverse-alternating-field electrophoresis, that the beta-amyloid precursor protein gene is located on chromosome 21 very near the 21q21/21q22 border and probably within the region of chromosome 21 that, when trisomic, results in Down syndrome.
Fetal weight does not seem to account for the lower maternal serum alpha-fetoprotein levels seen in fetuses with Down syndrome but may partially account for the lower levels seen in fetuses with trisomy 18.
The prion protein (PrP) is found in amyloid of animals with scrapie and humans with Creutzfeldt-Jakob disease; the beta protein is present in amyloid deposits in Alzheimer disease and Down syndrome patients.
These results suggest that the increase in CD18 expression by Trisomy 21 cells is due to gene dosage, and could influence the immune status of persons with Down syndrome.
Fifty couples and their children with Down syndrome (D.S.) were typed for HLA-A and HLA-B antigens and compared to 50 control families and 464 blood donors.
Amyloid B-protein/amyloid A4 is a peptide present in the neuritic plaques, neurofibrillary tangles and cerebrovascular deposits in patients with Alzheimer's disease and Down's syndrome (trisomy 21) and may be involved in the pathogenesis of Alzheimer's disease.
Fifty couples and their children with Down syndrome (D.S.) were typed for HLA-A and HLA-B antigens and compared to 50 control families and 464 blood donors.