APOLIPOPROTEIN-E4 ALLELE AND ALZHEIMERS-DISEASE - EXAMINATION OF ALLELIC ASSOCIATION AND EFFECT ON AGE AT ONSET IN BOTH EARLY-ONSET AND LATE-ONSET CASES
Pa. Locke et al., APOLIPOPROTEIN-E4 ALLELE AND ALZHEIMERS-DISEASE - EXAMINATION OF ALLELIC ASSOCIATION AND EFFECT ON AGE AT ONSET IN BOTH EARLY-ONSET AND LATE-ONSET CASES, Genetic epidemiology, 12(1), 1995, pp. 83-92
An increased frequency of the apolipoprotein E type 4 allele (APOE-4)
has previously been associated with both late-onset sporadic and late-
onset familial Alzheimer disease (AD) [Strittmatter et al. (1993) Proc
Natl Acad Sci USA 90:1977-1981; Saunders et al. (1993a) Neurology 43:
1467-1472]. To further investigate this association we genotyped affec
ted individuals from 92 separate AD pedigrees including both early- an
d late-onset cases. An increased frequency of the APOE-4 allele was fo
und only among the late-onset cases, both familial and sporadic, confi
rming the earlier reports. In addition, age at onset was significantly
decreased in the APOE-4 homozygotes (in late onset families) compared
to either APOE-4 heterozygotes or individuals not carrying an APOE-4
allele. We also observed a significantly decreased frequency of the AP
OE-2 allele in both the early- and late-onset familial cases. These re
sults strengthen the argument for a direct role of APOE in susceptibil
ity to AD. (C) 1995 Wiley-Liss, Inc.