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arXiv · 2010.00531

Did circoviruses intermediate the recombination between bat and pangolin coronaviruses, yielding SARS-CoV-2?

Nabil Abid·Giovanni Chillemi·Ahmed Rebai
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Abstract

Since the first reports of a coronavirus (CoV) disease 2019 (COVID-19) caused by severe acute respiratory syndrome virus (SARS-CoV-2) in Wuhan, Hubei province, China, scientists are working around the clock to find sound answers to the issue of its origin. While the number of scientific articles on SARS-CoV-2 is increasing, there are still many gaps as to its origin. All studies failed to find a coronavirus in other animals that is more similar to human SARS-COV2 than the bat virus, considered to be the primary reservoir. In this paper we address a new hypothesis, based on a possible recombination between a DNA and SARS-CoV viruses, to explain the rise of SRAS-CoV-2. By comparing SARS-CoV-2 and related CoVs with circoviruses (CVs), we found strong sequence similarity of the genomic region at the 3-end of Bat-CoV ORF1a and the origin of replication (Ori) of porcine CV type 2 (PCV2), as well as similar RNA secondary structures of the region encompassing the cleavage site of CoV S gene with the PCV2 Ori. This constitutes a primary evidence that supports a possible recombination, which occurrence might explain the origin of SARS-CoV-2.

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Nabil Abid, Giovanni Chillemi, Ahmed Rebai. 2020-09-29. Did circoviruses intermediate the recombination between bat and pangolin coronaviruses, yielding SARS-CoV-2?. https://arxiv.org/abs/2010.00531

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