ИСТИНА

Background/objectives: Coronavirus infection (COVID-19) is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). According to WHO (February 10, 2023), there are about 755 million confirmed cases of COVID-19, including more than 6.8 million deaths. Several risk factors have been associated with the severity of COVID-19, including patients with diabetes, hypertension, and other comorbidities. An important factor is also the genetic predisposition and the role of genetic variants. The aim of this study was to investigate the association of polymorphisms in the genes of paraoxonase 1(PON1) and nitric oxide synthase 3(NOS3), which are enzymes with antioxidant activity, with the severity of COVID-19. Methods: Genotyping of DNA samples isolated from blood cells of 110 COVID-19 patients (55 mild, 55 severe cases) was carried out by allele specific RT-PCR. Results: Significant associations of PON1 (Q192R-rs662) (p = 0.005) and NOS3 (T786C-rs2070744) (p = 0.035) polymorphisms with the severity of COVID-19 were found. Carriers of PON1 rs662 (QQ) genotype have a more severe course of COVID-19 (OR = 2.323; 95% CI [1.095–4.973]). The TT genotype of NOS3 rs2070744 was associated with severe cases (OR = 2.719; 95% CI [1.238-5.970]), while the TC genotype was more common in mild cases (OR = 0.381; 95% CI [0.176-0.823]). Conclusion: The obtained data indicates the importance of PON1 and NOS3 genetic variants in predicting the severity of COVID-19 symptoms.