Evaluating the MT-CYB and MT-ATP6 variations in COVID-19 patients: A case-control study

The complications and lingering effects of COVID-19 have caused a global health crisis, prompting intense investigations into the mechanism by which SARS-CoV-2 causes the disease. The majority of symptoms associated with this infectious disease are linked to mitochondrial dysfunction, and recent studies indicate that SARS-CoV-2 can impair host mitochondrial function. This study aims to investigate mutations in the MT-CYB and MT-ATP6 genes of mtDNA in COVID-19 patients and their association with disease outcomes. Out of 110 individuals enrolled, 30 were diagnosed with COVID-19, while the remaining 80 were healthy. Following DNA isolation from the blood samples, the MT-CYB and MT-ATP6 genes were amplified through PCR, purified, and sequenced using Sanger sequencing. In the MT-CYB gene, 9 distinct mutations were found. Among these, novel mutation m.14942A > C was more prevalent in COVID-19-positive individuals than COVID-19 negative controls (p = 0.012 < 0.05) and exhibited a significant correlation with the disease as OR (95% CI) = 19.75 (2.264-172.246). According to in-silico analyses, this mutation is deemed deleterious and decreases the stability of the CYB protein. In case of the MT-ATP6 gene, among the identified 8 mutations, the m.8744T > G mutation was higher in COVID-19-positive individuals than healthy controls (p = 0.009 < 0.05) and showed a significant correlation with the disease: OR (95% CI) = 24.04 (2.81-205.62). According to in-silico analyses, this mutation is found to be pathogenic and reduces the stability of the ATP6 protein. In conclusion, one novel mtDNA mutation was identified in this study, and some of the mutations identified in the MT-CYB as well as MT-ATP6 genes, including the novel mutation, are relatively common in the COVID-19 patient group. Moreover, the findings demonstrated that these mutations may contribute to the pathogenesis of COVID-19.