In the wake of the ongoing coronavirus pandemic ravaging the planet, a team of researchers have discovered a gene that may be closely related to origin and evolution of SARS-CoV-2 of COVID-19. The gene has previously been uncharacterized within the SARS-CoV-2 genome.
Researchers have named the newly identified gene ORF3c, which is an example of an overlapping gene. Overlapping genes (OLGs) have somewhat been overlooked in the past, despite indications of their link with origin of viral pandemics, according to authors of the research.
The preliminary analysis that SARS-CoV-2 contains an overlapping gene require more attention, say researchers. In particular, this is because contribution of overlapping gene may be more in the emergence of zoonotic viruses that is currently realized.
Questions of Jump of COVID-19 coronavirus from Animals to Human Remain Unanswered
Meanwhile, since the outbreak of COVID-19 in Wuhan in December 2019, many questions how the virus evolved to jump from animals to humans remain unanswered.
The understanding of potential mechanisms requires a thorough understanding of viral genomes, nonetheless, the emergence of overlapping genes (OLGs) remains an under-investigated area.
Although viral OLGs are common and have been linked with start of pandemics, they have largely been overlooked in studies pertaining to emerging pathogens.
Anatomically, overlapping genes offer several advantages. They enable an existing stretch of protein-coding nucleotides to encode another new protein in a different reading frame. The overprinting ameliorates the compression of genomic information and may present a significant genetic advantage. This is because frameshifted sequences conserve certain properties of proteins.
Nonetheless, sequence analysis of overlapping genes is complicated. This is because one mutation may result in alteration of two proteins. Meanwhile, genome annotation techniques tend to miss overlapping genes. This is because OLGs favor one open reading frame within a given area of the genome.