METHODS: In the present study, eight VDR single nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 500 COVID-19 patients in Iran, including 160 asymptomatic, 250 mild/moderate, and 90 severe/critical cases. The association of these polymorphisms with severity, clinical outcomes, and comorbidities were evaluated through the calculation of the Odds ratio (OR).
RESULTS: Interestingly, significant associations were disclosed for some of the SNP-related alleles and/or genotypes in one or more genetic models with different clinical data in COVID-19 patients. Significant association of VDR-SNPs with signs, symptoms, and comorbidities was as follows: ApaI with shortness of breath (P ˂ 0.001) and asthma (P = 0.034) in severe/critical patients (group III); BsmI with chronic renal disease (P = 0.010) in mild/moderate patients (group II); Tru9I with vomiting (P = 0.031), shortness of breath (P = 0.04), and hypertension (P = 0.030); FokI with fever and hypertension (P = 0.027) in severe/critical patients (group III); CDX2 with shortness of breath (P = 0.022), hypertension (P = 0.036), and diabetes (P = 0.042) in severe/critical patients (group III); EcoRV with diabetes (P ˂ 0.001 and P = 0.045 in mild/moderate patients (group II) and severe/critical patients (group III), respectively). However, the association of VDR TaqI and BglI polymorphisms with clinical symptoms and comorbidities in COVID-19 patients was not significant.
CONCLUSION: VDR gene polymorphisms might play critical roles in the vulnerability to infection and severity of COVID-19, probably by altering the risk of comorbidities. However, these results require further validation in larger studies with different ethnicities and geographical regions.
METHODS: Six unique siRNAs with three each targeting different regions of IE2 (ie2a, ie2b and ie2c) and DNA polymerase (dpa, dpb and dpc) were prepared and tested for antiviral activities. The efficacy as an antiviral was determined in in-vitro by measuring TCID50 virus titer, severity of virus-induced cytopathic effect (CPE), intracellular viral genome loads by droplet digital PCR, the degree of apoptosis in siRNA-treated cells and relative expression of viral mRNA in infected Rat Embryo Fibroblast (REF) cells.
FINDINGS: Remarkably, the siRNAs: dpa, dpb and IE2b, significantly reduced virus yield (approximately >90%) compared to control group at day 18 post infection (p.i). Changes in CPE indicated that DNA polymerase siRNAs were capable of protecting cells against CMV infection at day 14 p.i with higher efficiency than GCV (at the concentration of 300 pmol). Gene expression analysis revealed a marked down regulation of the targeted DNA polymerase gene (73.9%, 96.0% and 90.7% for dpa, dpb and dpc siRNA, respectively) and IE2 gene (50.8%, 49.9% and 15.8% for ie2a, ie2b and ie2c siRNA, respectively) when measured by RT-qPCR. Intracellular viral DNA loads showed a significant reduction for all the DNA polymerase siRNAs (dpa: 96%, dpb: 98% and dpc:92) compared to control group (P