Toll-like Receptor 3 c.1377C/T and -7C/A Polymorphisms Associated with COVID-19 and COVID-19 Severity

Abstract

Chinese officials have reported the novel coronavirus to the world health organization, which is called the SARS-CoV-2. Toll-like receptor 3 (TLR3) induces antiviral immune responses via the production of type I interferons and inflammatory cytokines. In this study, we aimed to examine TLR3 c.1377C/T and -7C/A polymorphisms in COVID-19 and the association between some clinical parameters. We investigated the frequencies of TLR3 (c.1377C/T and -7C/A) polymorphisms in 150 patients with COVID-19 and 171 healthy individuals as controls. We performed polymerase chain reaction (PCR) based on restriction fragment length polymorphism (RFLP). We also investigated whether TLR3 c.1377C/T and-7C/A were associated with the severity of COVID-19. In addition, CHAID tree-based classification algorithm was created to investigate the severity of the patients in our study. TLR3 c.1377C/T TT genotype frequencies were statistically significant between cases and controls (p= 0.02). For TLR3 -7C/A polymorphism, the findings showed a statistically significant difference in A allele frequencies (p= 0.03). There was a statistically significant difference in the distribution of TLR3 -7C/A CA genotype frequency (p= 0.04). Our findings suggest that TLR3 c.1377C/T and -7C/A polymorphisms may be important on susceptibility or clinical course of COVID-19.