Assessing the correlation between SNP rs1800795 genotypes to serum Interleukin- 6 levels among COVID-19 patients in Iraq


  • Nawal M. Utba
  • Tamara Adnan Abed
  • Ali H. Abdulkarem



COVID-19, interleukin-6, SNP rs1800795, cytokines, gene polymorphism


Introduction and Aim: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) induces very high-inflammatory responses which is a major cause of COVID-19 disease severity and death. Interleukin-6 (IL-6), among other patient proinflammatory cytokines, especially its genomic polymorphisms that affect the body's immune system, can influence the course of infectious diseases. The aim of this study was to evaluate the relationship between IL-6 and COVID-19 disease in Iraqi patients.


Materials and Methods: This study included a total of 100 Covid-19 infected patients (50 with moderate and 50 with severe infection), and 50 healthy individuals (controls) from Iraq. DNA isolated from blood samples of each participant was subjected to PCR amplification of the SNP rs1800795 fragment of the Interleukin- 6 gene, which was further genotyped for the -174 G/C polymorphism. Serum interleukin- 6 (IL-6) levels were evaluated to assess the correlation between the   IL-6 levels and the SNP rs1800795 genotypes.


Results: The levels of IL-6 in sera of moderate and critical COVID-19 groups were significantly higher and increased with intensity of COVID-19 disease. Hardy-Weinberg equilibrium analysis showed the SNP rs1800795 genotypes (GG, GC, and CC) to remain constant in COVID-19 patients and controls. The study also showed no significant differences (p>0.05) for the IL-6 serum levels in association to the three genotypes.


Conclusion: SNP rs1800795 genotypes do not pose a risk factor for developing severe COVID-19 in the Iraqi population. Increased age, on the other hand, could be considered a risk factor for COVID-19 outcomes. COVID-19 vaccination is highly efficient in preventing severe COVID-19 infection.

Author Biographies

Nawal M. Utba

Department of Biology, College of Science, University of Baghdad, Baghdad, 10071, Iraq

Tamara Adnan Abed

Department of Biology, College of Science, University of Anbar, Anbar, Iraq

Ali H. Abdulkarem

Department of Biology, College of Science, University of Anbar, Anbar, Iraq


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How to Cite

M. Utba N, Adnan Abed T, H. Abdulkarem A. Assessing the correlation between SNP rs1800795 genotypes to serum Interleukin- 6 levels among COVID-19 patients in Iraq. Biomedicine [Internet]. 2023 Nov. 9 [cited 2023 Dec. 2];43(5):1490-5. Available from:



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