Effect of IL-6 polymorphism on risk of Alzheimer disease: genotype-phenotype association study in Japanese cases.
Interleukin-6 (IL-6), an inflammatory cytokine might be involved in the pathophysiology of Alzheimer disease (AD); several studies have reported that the "C allele of IL-6 variable number of tandem repeat polymorphism" (IL-6vntr) delayed initial onset of AD and also decreased its risk per se. Another polymorphism, G/C allele of IL-6 gene promoter region (IL-6prom), is also a candidate because it has an influence on the regulation of plasma IL-6 concentration. We examined these IL-6 polymorphisms in 128 Japanese AD cases and 83 control cases using a PCR-RFLP method. The results showed the frequency of the IL-6prom G allele was significantly increased in AD, although IL-6vntr polymorphism was not. Plasma IL-6 concentration of the AD cases was also significantly higher than that of the control cases. Moreover, the IL-6prom G allele-positive AD patients showed a tendency to have higher IL-6 concentration in the AD group. These findings suggest that the IL-6prom G allele which may affect plasma IL-6 concentration might be a risk factor for sporadic AD in Japanese.
Shibata
Nobuto
N
Department of Psychiatry, Juntendo University School of Medicine, Tokyo, Japan. nobuto.shibata@nifty.ne.jp
Ohnuma
Tohru
T
Takahashi
Tadashi
T
Baba
Hajime
H
Ishizuka
Takuya
T
Ohtsuka
Mieko
M
Ueki
Akira
A
Nagao
Masatsugu
M
Arai
Heii
H
D000368:Aged; D000544:Alzheimer Disease / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D015850:Interleukin-6 / Q000235:genetics*; D007564:Japan; D008297:Male; D018598:Minisatellite Repeats; D010641:Phenotype; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D012307:Risk Factors
D015850:Interleukin-6