RESEARCHERS discovered that a new hidden gene in the SARS-CoV-2 virus that causes COVID-19 may have contributed to its unique biology and pandemic potential. SARS-CoV-2 only has about 15 genes, and knowing more about this and other overlapping genes–or “genes within genes” could have a significant impact on fighting the virus, scientists say. The new gene is described in the journal eLife.
The researchers identified ORF3d, a new overlapping gene in SARS-CoV-2 that has the potential to encode a protein that is longer than expected by chance alone. They found that ORF3d is also present in a previously discovered pangolin coronavirus, perhaps reflecting repeated loss or gain of this gene during the evolution of SARS-CoV-2 and related viruses. ORF3d has also been independently identified and shown to elicit a strong antibody response in COVID-19 patients, demonstrating that the new gene’s protein is produced during human infection.
“Overlapping genes may be one of an arsenal of ways in which coronaviruses have evolved to replicate efficiently, thwart host immunity, or get themselves transmitted,” said lead author Chase Nelson, a postdoctoral researcher at Academia Sinica in Taiwan and a visiting scientist at the American Museum of Natural History. “Knowing that overlapping genes exist and how they function may reveal new avenues for coronavirus control, for example through antiviral drugs.”