Association between TNF-alpha promoter polymorphism and Helicobacter pylori cagA subtype infection.
OBJECTIVE
To assess the importance of tumour necrosis factor alpha (TNF-alpha) promoter polymorphism in relation to infection with the cytotoxin associated gene A (cagA) subtype of Helicobacter pylori within a dyspeptic Korean population.


METHODS
Eighty three patients with gastric disease and 113 healthy controls were studied. The DNA from gastric biopsy specimens was analysed by H pylori specific and cagA specific polymerase chain reaction (PCR). To characterise TNF-alpha polymorphism at positions -308 and -238, PCR based restriction fragment length polymorphism analysis was performed.


RESULTS
Helicobacter pylori infection was closely correlated with G to A transition at position -308 of the TNF-alpha promoter when compared with healthy controls (odds ratio (OR), 2.912; 95% confidence interval (CI), 1.082 to 7.836; p = 0.034). Although TNF-alpha -308 polymorphism in patients with H pylori was not significantly different from that in patients without H pylori, the -308A polymorphism was strongly associated with H pylori cagA subtype infection when compared with the polymorphism in cagA negative H pylori infection (OR, 8.757; 95% CI, 1.413 to 54.262; p = 0.019) and healthy controls (OR, 3.683; 95% CI, 1.343 to 10.101; p = 0.011). G to A genetic change at position -238 of the TNF-alpha gene was not significantly associated with H pylori cagA subtype infection. In addition, genetic polymorphisms at both sites of the TNF-alpha promoter in patients with H pylori infection did not correlate with the severity of disease.


CONCLUSIONS
TNF-alpha -308A polymorphism was significantly related to infection with the H pylori cagA subtype in Korean patients with gastric disease.
Yea
S S
SS
The Paik-Inje Memorial Institute for Biomedical Science, Inje University, Pusan 614-735, Korea.
Yang
Y I
YI
Jang
W H
WH
Lee
Y J
YJ
Bae
H S
HS
Paik
K H
KH
D000942:Antigens, Bacterial; D001426:Bacterial Proteins / Q000235:genetics*; D015373:Bacterial Typing Techniques; D020022:Genetic Predisposition to Disease; D005838:Genotype; D016481:Helicobacter Infections / Q000150:complications / Q000235:genetics* / Q000382:microbiology; D016480:Helicobacter pylori / Q000145:classification / Q000235:genetics*; D006801:Humans; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D011401:Promoter Regions, Genetic; D013272:Stomach Diseases / Q000235:genetics* / Q000382:microbiology; D013274:Stomach Neoplasms / Q000235:genetics / Q000382:microbiology; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D014409:Tumor Necrosis Factor-alpha; C080866:cagA protein, Helicobacter pylori