Decreased frequency of apolipoprotein E epsilon4 allele from Northern to Southern Europe in Alzheimer's disease patients and centenarians.

Apolipoprotein E (apoE) polymorphism was studied in 79 sporadic late onset Alzheimer's disease (LOAD) patients, 125 unrelated caregivers or volunteers (19±80 years), and 67 centenarians from Apulia, Southern Italy. The frequency of apoE 12 allele was higher in centenarians than in LOAD patients, while 14 was lower. In middle-aged adults, the 14 allele frequency was higher than in centenarians. The 14 allele frequency was lower in healthy adults than in LOAD patients, while 12 was higher. Compared with the allele frequencies of Northern and Central European countries, a geographic trend for 13 and 14 alleles in LOAD and middle-aged adults was observed. The frequency of 13 increased from Northern to Southern Europe, while 14 decreased signi®cantly. In centenarians, 12 showed a North±South increasing pattern, while 14 was in opposite trend.