Polymorphism in the promoter region of tumor necrosis factor-alpha gene is associated with severe meliodosis

Melioidosis is an important infectious disease endemic in Southeast Asia and the Northern territories of Australia. Septicemic melioidosis, is the leading cause of fatality from community acquired septicemia in northeastern part of Thailand where death often occurs within a few days after hospitalization. The present study was carried out to investigate the polymorphisms of the position -308 promoter region of the TNF-alpha gene, as well as of the intron 1 of the TNF-beta gene in patients with melioidosis compared with normal uninfected controls in the same endemic area. The gene frequency of TNF2 allele was significantly higher in melioidosis patients compared with control subjects (p = 0.0097, relative risk 2.32). The increase in TNF2 allele in melioidosis patients was found in both heterozygous and homozygous forms. In addition, the increase in TNF2 allele was most apparent in patients who had fatal outcome from septicemic melioidosis (p = 0.017), but was also observed with lesser degree in other groups of melioidosis patients. However, no difference in the frequency of TNF-beta polymorphism the melioidosis patients was observed.