Apolipoprotein E ε4 allele distribution in alcoholic dementia and in Alzheimer's disease in Japan

The apolipoprotein E ε4 allele has been associated with both familial and sporadic Alzheimer's disease (AD). Given its possible role in nerve repair and growth, it is plausible that apolipoprotein E may be a common denominator in the pathogenesis of several dementing diseases. Therefore, we investigated ε4 frequencies in demented and nondemented alcoholics, as well as in patients with sporadic AD and controls in Japan. No significant difference in allele frequencies was found between demented and nondemented alcoholics and controls, while a significant association was demonstrated between AD and the ε4 allele. These results support a specific role of ε4 in the pathogenesis of AD, rather than a more general role for ε4 in dementing illnesses.