Modest Evolutionary Changes of the SARS-CoV-2 Genome in Bangladesh

Abstract

Background: The human-to-human transmissive nature of SARS-CoV-2 makes Bangladesh, as well as the other South Asian regions, vulnerable to the ongoing pandemic of COVID-19 due to their high population densities. The present study was designed based on the genome wide analysis of Bangladeshi and other South Asian isolates. Complete sequences of SARS-CoV-2 were retrieved from the EpiCoV database in order to identify molecular features demonstrating the evolutionary trail and mutation rate.Result: The complete genome mutation rate of the Bangladeshi isolates was estimated to be 0.49E-3 nucleotide substitutions/site/year. A higher mutation rate was found in the non-structural protein-coding genes at: ORF6 (10.29E-3), ORF7a (31.81E-3), and ORF8 (18.35E-3). In contrast, the mutation rates of the structural protein-coding genes were relatively low at: M (1.14E-3), S (1.47E-3), E (3.35E-3), and N (4.59E-3).Conclusions: A comparison of Bangladeshi and other South Asian isolates demonstrated that there were limited mutational changes in the SARS CoV-2 genome. Knowledge of the Southeast Asian SARS CoV-2 evolutionary genome will help in selecting future vaccine candidates and designing therapeutic drug targets.