Research recently published in the scientific journal eLife revealed the existence of a “mysterious” gene discovered within another gene in the coronavirus SARS-CoV-2, the cause of covid-19. Called ORF3d, it is an overlapping gene (PLO), a type of nucleotide sequence that is very common in pandemics, but, so far, forgotten.
Made by a group of scientists led by Chase Nelson, from the Museum of Natural History in New York, USA, the discovery “may reveal new ways of controlling the virus, such as antiviral drugs,” says the study. It is also possible that the new gene detected may be able to contribute to the unique biology of the virus and its pandemic potential.
The importance of discovering the new virus
In assessing the new coronavirus pandemic, scientists around the world are trying to understand the properties that allow these animal viruses to cross the species boundary and spread within human organisms. Such an understanding depends on a perfect understanding of viral genomes.
According to Nelson, “the overlapping of genes is perhaps one of the ways in which coronaviruses have evolved to replicate efficiently, disrupt the immunity of those infected and transmit themselves”. An overlapping gene remains “hidden” within the nucleotide chain, due to how it overlaps with the sequences of the other genes.
Although relatively common within viruses, OLPs are difficult to detect because most existing computer programs are not originally designed to find them. Furthermore, since the SARS-Cov-2 genome is very long, “they may be more likely to contain this ‘genomic farce’,” says Nelson.