IL-6 gene polymorphism in Russians patients with COVID-19 in the Chelyabinsk region

The severe acute respiratory syndrome coronavirus - 2 (SARS-CoV-2) pandemic that caused the 2019 coronavirus disease (COVID-19) outbreak has become a major public health concern worldwide. Host genetic factors are known to be associated with the severity of COVID-19. Finding di erences between asymptomatic and severely ill patients with COVID-19 contributes to a broader understanding of the disease and may help develop new treatments. Interleukin-6 (IL-6) is a multifunctional cytokine secreted by many cell types, including monocytes/macrophages, dendritic cells, broblasts, endothelial cells, B and T cells, in response to in ammatory stimuli and viral infections. IL-6 plays a key role in exacerbating the in ammatory response in SARS-CoV-2 infection. Elevated serum concentrations of IL-6 and other cytokines are signs of severe COVID-19. The various e ects of IL-6 are related to cytokine concentration determined by gene polymorphisms. In this study, we compared the distribution of alleles and genotypes of the IL-6 gene in patients with di erent forms of severity of COVID-19 tuberculosis. The following methods were used: isolation of DNA samples from whole blood, genotyping of the studied gene polymorphisms using polymerase chain reaction, and agarose gel electrophoresis. We found that in patients with a mild form, the frequency of the G/G genotype, which is responsible for a high level of cytokine production, is lowered in comparison with patients with a more severe course. With a group of patients with a severe form, the di erences are at the level of a trend.