Allelic variation of apolipoprotein E in Japanese sporadic Creutzfeldt-Jakob disease patients.

We analyzed apolipoprotein E (apo E) genotypes in 53 Japanese sporadic Creutzfeldt-Jakob disease (CJD) patients and 100 normal controls using the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods. The apo E allelic frequencies in Japanese sporadic CJD patients and our control population were as follows: epsilon 2, 6.6% versus 7.5%; epsilon 3, 82.1% versus 81.5%; epsilon 4, 11.3% versus 11.0%. The mean ages at onset in Japanese sporadic CJD patients were as follows: epsilon 3/epsilon 3, 63.8 years; epsilon 3/epsilon 4, 66.3 years; epsilon 2/epsilon 3, 68.6 years. These results indicate that there is no association between apo E genotype and sporadic CJD in Japan.