Association between SNP rs4986790 and COVID-19 infection severity among Baghdad patients


  • Marwa Fadil Jabber
  • Anfal Mohammed Khudhair



COVID-19, SARS-CoV-2, polymorphism, Toll-like receptor 4, SNP rs4986790


Introduction and Aim: COVID-19, an infectious disease caused by the SARS-CoV-2 coronavirus, is distinguished by the manifestation of severe acute respiratory syndrome. Toll-like receptors (TLRs) are signaling molecules that play crucial roles in the innate immune system through their recognition of pathogen-associated molecular patterns in diverse microorganisms, including coronaviruses. The primary aim of this research was to investigate the plausible association between the TLR4 gene Asp299Gly polymorphism and the degree of infection severity among individuals who contracted COVID-19 in Baghdad, Iraq.  


Materials and Methods: This cross-sectional prospective study was carried out in Baghdad to investigate the Asp299Gly polymorphism within the TLR4 gene in a cohort of 90 patients diagnosed with Covid-19. Out of the total number of patients, 45 individuals exhibited symptoms indicative of a moderate infection, while the remaining 45 patients presented with a severe illness. The Asp299Gly polymorphism was analyzed using polymerase chain reaction (PCR) technique and restriction fragment length polymorphism (RFLP).


Results: Genotyping for the Asp299Gly polymorphism showed only one among the 90 (1.1%) Covid-19 patients tested to be positive. No significant association was seen between covid-19 severity and Asp299Gly (P = 0·31) polymorphism.


Conclusion: Our study found no association between SNP rs4986790 of TLR4 gene and COVID-19 severity among Covid-19 patients in Baghdad city.

Author Biographies

Marwa Fadil Jabber

Department of Biology, Al-Iraqia University, College of Medicine, Baghdad, Iraq

Anfal Mohammed Khudhair

Department of Biology, Al-Iraqia University, College of Medicine, Baghdad, Iraq


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How to Cite

Fadil Jabber M, Mohammed Khudhair A. Association between SNP rs4986790 and COVID-19 infection severity among Baghdad patients. Biomedicine [Internet]. 2023 Aug. 30 [cited 2023 Oct. 4];43(4):1188-92. Available from:



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