Effect of tumour necrosis factor-alpha and interleukin-6 promoter polymorphisms on course of Crimean-Congo hemorrhagic fever in Turkish patients

J Vector Borne Dis. 2015 Mar;52(1):30-5.

Abstract

Objective: In this case-control study, we investigated whether IL-6 (-174G/C) and TNF-α (-308G/A) gene polymorphisms affect the clinical course and outcome of CCHF.

Methods: Total 150 patients with CCHF and 170 controls were examined in this study. Genotyping of these polymorphisms were performed by PCR-RFLP methods.

Results: We found no statistically significant differences in genotype and allele frequencies of these polymorphisms between patients and controls [(χ2 = 1.31, p = 0.51 for TNF-α) and (χ2 = 2.61, p = 0.27 for IL-6)]. Either TNF-α AA or IL-6 CC genotypes in dead cases were not observed in this study. Frequency of heterozygous genotypes in both IL-6 (GC) and TNF-α (GA) was higher in dead patients than living patients. However, the difference was not statistically significant. A significant difference was found in AST levels and INR when compared to patients with CCHF who died and who survived [OR = 13.9 (95% CI = 1.79-107) for INR, p = 0.01] and [OR = 23.3 (95% CI = 3.62-149) for AST, p = 0.001], respectively.

Conclusion: We did not find a significant association of IL-6 -174G/C and TNF-α -308G/A polymorphisms on the prognosis of CCHF and mortality in this study. We suggest that AST and INR may be important biomarkers for determining the risk of severity and death as a result of infection with Crimean-Congo hemorrhagic fever virus (CCHFV).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Case-Control Studies
  • Female
  • Gene Frequency
  • Genotype
  • Hemorrhagic Fever Virus, Crimean-Congo / genetics*
  • Hemorrhagic Fever, Crimean / pathology*
  • Hemorrhagic Fever, Crimean / virology
  • Humans
  • Interleukin-6 / genetics*
  • Male
  • Middle Aged
  • Polymerase Chain Reaction
  • Polymorphism, Genetic*
  • Polymorphism, Restriction Fragment Length
  • Tumor Necrosis Factor-alpha / genetics
  • Turkey
  • Young Adult

Substances

  • IL6 protein, human
  • Interleukin-6
  • Tumor Necrosis Factor-alpha