Apolipoprotein E gene variants of Alzheimer's disease and vascular dementia patients in a community population of Nanking.

To explore apolipoprotein E gene variants distribution among the patients of Alzheimer's disease and vascular dementia for the elderly community population in Nanking, the polymerase chain reaction and restriction fragment length polymorphism techniques were employed to analyze the gene frequency of apolipoprotein E (ApoE) for 113 cases with Alzheimer's disease (AD), 85 cases with vascular dementia (VaD), 147 cases with questionable dementia (QD), and 396 dementia-free controls. It was found that ApoE ε4 gene container (37.17%) and allele frequency (21.