  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.
