Assessment of intercontinents mutation hotspots and conserved domains within SARS-CoV-2 genome.

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 pathogen, has led to waves of global pandemic claiming lives and posing a serious threat to public health and social cum physical interactions. To evaluate the mutational landscape and conserved regions in the genome of the causative pathogen, we analysed 7213 complete SARS-CoV-2 protein sequences mined from the Global Initiative on Sharing All Influenza Data (GISAID) repository from infected patients across all regions on the EpiCov web interface. Regions of origin and the corresponding number of sequences mined are as follows: Asia - 2487; Oceania - 2027; Europe - 1240; Africa - 717; South America - 391; and North America - 351. High recurrent mutations, namely: T265I in non-structural protein 2 (nsp2), L3606F in nsp6, P4715L in RNA-dependent RNA polymerase (RdRp), D614G in spike glycoprotein, R203K and G204R in nucleocapsid phosphoprotein and Q57H in ORF3a with well-conserved envelope and membrane proteins, 3CLpro and spike S2 domains across regions were observed. Comparative analyses of the viral sequences reveal the prevalence P4715L and D614G mutations as the most recurrent and concurrent in Africa (97.20%), Europe (89.83%) and moderately in Asia (61.60%). Mutation rates are central to viral transmissibility, evolution and virulence, which help them to invade host immunity and develop drug resistance. Based on the foregoing, it is important to understand the mutational spectra of SARS-CoV-2 genome across regions. This will help in identifying specific genomic sites as potential targets for drug design and vaccine development, monitoring the spread of the virus and unraveling its evolution, virulence and transmissibility.

Mutational hotspots and conserved domains of SARS-CoV-2 genome in African population.

BACKGROUND: Since outbreak in December 2019, the highly infectious and pathogenic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused over a million deaths globally. With increasing burden, the novel coronavirus has posed a dire threat to public health, social interaction, and global economy. Mutations in the SARS-CoV-2 genome are moderately evolving which might have contributed to its genome variability, transmission, replication efficiency, and virulence in different regions of the world. RESULTS: The present study elucidated the mutational landscape in the SARS-CoV-2 genome among the African populace, which may have contributed to the virulence, spread, and pathogenicity observed in the region. A total of 3045 SARS-CoV-2 complete protein sequences with the reference viral sequence (EPI_ISL_402124) were mined and analyzed. SARS-CoV-2 ORF1ab, spike, ORF3, ORF8, and nucleocapsid proteins were observed as mutational hotspots in the African population and may be of keen interest in understanding the viral host relationship, while there is conservation in the ORF6, ORF7a, ORF7b, ORF10, envelope, and membrane proteins. CONCLUSIONS: The accumulation of moderate mutations (though slowly), in the SARS-CoV-2 genome as seen in this present study, could be a promising strategy to develop antiviral drugs or vaccines. These antiviral interventions should target viral conserved domains and host cellular proteins and/or receptors involved in viral invasion and replication to avoid a new viral wave due to drug resistance and vaccine evasion. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s43088-021-00102-1.

Contributory role of SARS-CoV-2 genomic variations and life expectancy in COVID-19 transmission and low fatality rate in Africa

Background: The novel coronavirus disease (COVID-19) has claimed lots of lives, posing a dire threat to global health. It was predicted that the coronavirus outbreak in the African population would be very lethal and result to economic devastation owing to the prevalence of immune-compromised population, poverty, low lifespan, fragile health care systems, poor economy, and lifestyle factors. Accumulation of mutations gives virus selective advantage for host invasion and adaptation, higher transmissibility of more virulent strains, and drug resistance. The present study determined the severe acute respiratory syndrome-2 (SARS-CoV-2) genomic variability and the contributory factors to the low COVID-19 fatality in Africa. To assess the SARS-CoV-2 mutational landscape, 924 viral sequences from the Africa region with their sociobiological characteristics mined from the Global Initiative on Sharing All Influenza Data (GISAID) database were analyzed. Results: Mutational analysis of the SARS-CoV-2 sequences revealed highly recurrent mutations in the SARS-CoV-2 spike glycoprotein D614G (97.2%), concurrent R203K, and G204R (65.2%) in the nucleocapsid phosphoprotein, and P4715L (97.2%) in the RNA-dependent RNA polymerase flagging these regions as SARS-CoV-2 mutational hotspots in the African population. COVID-19 is more severe in older people (> 65 years);Africa has a low percentage of people within this age group (4.36%). The average age of the infected patients observed in this study is 46 years with only 47 infected patients (5.1%) above 65 years in Africa in comparison to 13.12% in countries in other continents with the highest prevalence of COVID-19. Conclusions: Africa's young generation, the late incidence of the disease, and adherence to public health guidelines are important indicators that may have contributed to the observed low COVID-19 deaths in Africa. However, with the easing of lockdown and regulatory policies, daily increasing incidence in most countries, and low testing and sequencing rate, the epidemiology and the true impact of the pandemic in Africa remain to be unraveled. [ABSTRACT FROM AUTHOR] Copyright of Egyptian Journal of Medical Human Genetics is the property of Egyptian Society of Human Genetics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)