Alzheimer pathology of patients carrying apoliprotein E ε4 allele

A recent report suggested that brains of Alzheimer patients homozygous for APOE ε4 show increased amyloid pathology compared to APOE ε3 homozygotes. We studied APOE allele frequencies in 73 AD patients and 33 controls. We also investigated relation of APOE genotypes to β/A4 immunopositive plaques, cerebrovascular β/A4 deposition, neurons expressing paired helical filaments (PHFs), and synaptophysin-like immunopositivity in 22 neuropathologically verified AD patients. We also correlated APOE genotypes of definite AD patients to β/A4 immunoreactivity in dermal vessel walls detected in lifetime skin biopsy samples. APOE allele ε4 frequency was increased in AD compared to nondemented controls (0.37 vs. 0.11; p = 0.006). The number of β/A4 immunoreactive plaques, PHFs-containing neurons, the degree of cerebrovascular β/A4 deposition or synaptophysin-like immunoreactivity did not differ significantly in AD patients with or without ε4. β/A4 deposition in dermal vessel walls was more frequent in definite AD patients with ε4 (43%) than in patients without ε4 (22%). However, the difference did not reach the statistical significance.