[The apolipoprotein E genotype and Down's syndrome].
Some individuals with Down syndrome develop an Alzheimer-type dementia in the third and fourth decades of life. Dementia in Alzheimer disease has been associated with the presence of genotype epsilon 4/epsilon 4 in apolipoprotein E (apo E). By means of molecular analysis techniques genotypes in lipoprotein apo E were identified in 21 patients with Down syndrome. The results obtained showed that 76% of the studied population had the genotype epsilon 3/epsilon 3 and 9% genotypes epsilon 3/epsilon 4 and epsilon 2/epsilon 3. None of the cases was homozygous for the allele epsilon 4. The analysis of our data shows the absence of differences between the distribution of genotype apo E among the Down population studied and among general population. We therefore consider that the presence of the allele epsilon 4 has no influence on the manifestation of Alzheimer disease in patients with Down syndrome.
Rascón Trincado
M V
MV
Departamento de Pediatría, Facultad de Medicina, Salamanca.
González Sarmiento
R
R
Salazar A-Villalobos
V
V
D000328:Adult; D000483:Alleles; D000544:Alzheimer Disease / Q000235:genetics; D001057:Apolipoproteins E / Q000235:genetics*; D001483:Base Sequence; D017931:DNA Primers; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D005838:Genotype; D006720:Homozygote; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction
D001057:Apolipoproteins E; D017931:DNA Primers