Apolipoprotein-E genotype in normal aging, age-associated memory impairment, Alzheimer's disease and vascular dementia patients

Apolipoprotein-E (Apo-E) genotype and allele frequencies were evaluated in patients with late-onset probable Alzheimer's disease (LOAD; n = 64), early-onset probable Alzheimer's disease (LOAD; n = 32), possible Alzheimer's disease (pAD; n = 44), vascular dementia (VD; n = 12), age-associated memory impairment (AAMI; n = 15) and 40 healthy age-matched controls. APO-E was performed by polymerase chain reaction products digested by the restriction enzyme HhaI. A statistically significant increase of epsilon 4 frequency was found in LOAD as compared to the other groups, and in pAD with respect to controls, while VD and AAMI groups did not disclose any difference as regards to control subjects. Multivariate analysis showed a significant association of epsilon 4 with female gender. Our results confirm the increased frequency of epsilon 4 in both probable and possible LOAD, failing to show a similar trend in VD and AAMI. (C) 1997 Elsevier Science Ireland Ltd.