A study on genetic variation of RdRp and N genes in individuals under 18 years of age infected with COVID-19 in Samarra city, Iraq

COVID-19 infection was diagnosed by real-time PCR in one hundred eighty subjects out of two hundred seventy enrolled in this study. The mean age of the COVID-19 negative group was 10.91±4.7 years, while that of the positive was 10.91±4.68 years. The COVID-19 negatives reported a higher count for the B blood group (36 subjects), while the COVID-19 positives reported a higher count for the AB blood group (67 subjects). Both the COVID-19-positive and COVID-19-negative groups had a significant percentage of members (53.3% and 51.1%, respectively) who had no travel history. The serum markers; D-dimer, IgG, and IgM levels showed a very highly statistically significant difference (p ≤ 0.001) when COVID-negative and COVID-positive groups were compared. Regarding the 180 COVID-19 positive subjects, we observed that 50% of the samples expressed the N gene, whereas not all samples expressed the RdRp gene. The result suggests a non-significant association between the expression of the N gene in COVID-19-positive samples and the traveling history (p=0.78). The results indicated no statistically significant association between N gene expression and COVID-19-positive blood groups (p = 0.62). N gene expression did not significantly correlate with the infection period of COVID-19 positives (p=0.28). The N gene sequencing results showed that samples 1, 2, 3, 4, and 5 were 91%, 86%, 93%, and 92% alike with reference strains Acc. No: OR820929.1, PP933529.1, OW021474.1, OR820929.1, and OQ097163.1 in GenBank, in that order.