Association between gene polymorphisms of tumor necrosis factor and the susceptibility and prognosis of severe sepsis

Objective To determine the allele frequency and genotypic distribution of tumor necrosis factor (TNF)-α and TNF-β gene polymorphisms and serum TNF-α concentrations in the patients with severe sepsis. Methods Genotypes were determined in patients (n=56) and healthy controls (n=60) by means of restriction fragment length polymorphism analysis of polymerase chain reaction products. Serum concentrations of TNF-α were measured by ELISA. Results ①The TNF-α allele frequency and genotypic distribution in the patients with severe sepsis were comparable with those values found in normal individuals (0.25 vs 0.067, P0.05, RR=4.667). No significant differences were found in TNF-β gene polymorphism. ②TNF-α2 frequency was significantly higher in nonsurvivors with septic shock than in survivors (0.429 vs 0.19, P0.05, RR=4.163). No significant differences were found in TNF-β gene polymorphism between the two groups. ③There were significant differences in baseline concentrations of TNF-α between survivors and nonsurvivors [(65.24 ± 6. 55)pg/mL vs (76.54±7. 45)pg/mL,P0.05].④ TNF-α concentration correlated with TNF-α polymorphism, but not with TNF-β polymorphism. Conclusion Some associations between the susceptibility and prognosis of sepsis and the TNF-α polymorphisms were found, but no associations were found between TNF-β gene polymorphism and sepsis.