Association of tumor necrosis factor β genetic polymorphism and sepsis susceptibility

The association of the tumor necrosis factor beta (TNF-beta) Ncol genetic polymorphism with susceptibility to sepsis was evaluated in 60 consecutive patients diagnosed with sepsis and in 148 healthy blood donors. Genomic DNA was extracted from peripheral blood cells and a 782 base-pair fragment of the TNE-beta gene was amplified by PCR. The PCR products were subjected to Ncol restriction digestion and analysed by restriction fragment length polymorphism analysis. Tumor necrosis factor alpha (TNF-alpha) and the C-reactive protein (CRP) serum levels were also determined by ELISA and nephelometry, respectively. Among the septic patients, the allelic frequencies of TNFB1 and TNFB2 were 0.2833 and 0.7166, respectively, and they differed from those observed in the blood donors (p=0.0282). The TNFB2 allele frequency was higher in the septic patients than in the blood donors (odds ratio=1.65 (Cl 95% 1.02-2.69), p=0.0315]. The TNF-alpha and CRP serum levels and the APACHE 11 and SOFA clinical scores did not differ in the patients with the TNFB1 or TNFB2 alleles (p>0.05). The results suggest that the TNFB2 allele is associated with susceptibility to sepsis, but it was not found to be associated with the immunological and clinical biomarkers of the disease.