Tokyo centenarian study 4 apolipoprotein E phenotype in Japanese centenarians living in the Tokyo metropolitan area

To examine the relationship between apolipoprotein E (apoE) phenotype and life span, we measured the frequency of the apoE phenotype and allele in 54 Japanese centenarians who lived in the Tokyo metropolitan area in 1994, 1995, and 1996. The control group consisted of 973 subjects, 883 healthy volunteers who were described previously and 90 healthy people who came to the Keio health consulting center. The apoE phenotypes in the centenarians was 2 E2/E2 (3.7%), 5 E2/E3 (9.3%), 38 E3/E3 (70.4%), and 9 3E/E4 (16.7%). No other phenotype was observed. In the control group, the phenotypes were 2 E2/E2 (0.2%), 57 E2/E3 (5.9%), 712 E3/E3 (73.2%), and 179 E3/E4 (18.4%). The frequency of E2 was higher in the centenarians. The frequencies of the apoE allele in the centenarians and the control subjects were ε2 8.3% vs. 3.5%, ε3 83.3% vs. 85.4%, and ε4 8.3% vs, 10.9%. The frequency of the apoE allele differed significantly between centenarians and control subjects (χ²= 6.84, p=0.033). Levels of serum cholesterol and apolipoprotein B were significantly lower in the E2/E2 + E2/E3 centenarians. Studies of the frequency of the apoE allele in Japanese, French, and Finnish subjects showed that ε2 is more frequent and ε4 is less frequent in centenarians. These data show the apoE phenotype may affect life span: ε2 is positively and ε4 is negatively associated with longevity.