[ad_1]
Compiled by Zakiyah Ebrahim
|
Health24
12 Nov 2020, 04:45
- Scientists have discovered a ‘hidden’ gene in the genetic code of SARS-CoV-2
- This overlapping gene, the team said, is unlikely to be detected by T cells in the human body.
- Previous findings have also found mysterious genes, all useful in the search for treatments and vaccines.
Researchers at the American Museum of Natural History have identified a new “hidden” gene in SARS-CoV-2, the virus that causes Covid-19, and they say this may explain why it is so infectious.
The discovery of the “overlapping gene,” called ORF3d, could have a significant impact on how we fight the virus, the research team wrote. Overlapping genes (OLG) are a type of ‘gene within a gene’, effectively hidden in a chain of nucleotides, ScienceAlert Explain.
“Gene overlap may be one of the ways coronaviruses have evolved to replicate efficiently, thwart host immunity, or pass on,” 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 there are overlapping genes and how they work can reveal new avenues for coronavirus control, for example through antiviral drugs.”
Their findings were published in the journal eLife.
T cells are unlikely to detect ORF3d
According to the team’s findings, the newly discovered gene is present in a previously discovered pangolin coronavirus. This, they say, possibly reveals the repeated loss or gain of this gene during the evolution of the new coronavirus, as well as related viruses.
The gene has also been shown to elicit a strong antibody response in Covid-19 patients, the researchers said, demonstrating that its protein is made during human infection.
“We don’t yet know its function or if there is clinical significance,” Nelson said. “But we predict that this gene is relatively unlikely to be detected by a T-cell response, in contrast to the antibody response.
“And maybe that has something to do with how the gene came to be.”
T cells are “natural killers” whose job it is to find infected cells in the human body and destroy them, Professor Thomas Scriba, deputy director of immunology and laboratory director of the South African Tuberculosis Vaccine Initiative at the University of Cape Town. Health24.
Explanation of the mystery genes
Overlapping genes are difficult to detect, the researchers explained, as they are virtually hidden from view in the virus genome and are therefore easily missed.
Most scientific computer programs are not designed to find them, they said, although OLGs are relatively common in DNA and RNA viruses, in part because RNA viruses (such as SARS-CoV-2) have a high rate of mutation.
“The lack of overlapping genes puts us in danger of overlooking important aspects of viral biology,” Nelson said.
“In terms of genome size, SARS-CoV-2 and its relatives are among the longest RNA viruses out there. Therefore, they are perhaps more prone to ‘genomic tricks’ than other RNA viruses.”
Previous discoveries about hidden mutations
Earlier this year, scientists in a separate study also suggested that SARS-CoV-2 exploits a rare, ‘silent’ (hidden) genetic mutation in certain people, and said it may provide clarity on why two young individuals and Healthy people can be so differently affected by the virus, Health24 reported.
In another groundbreaking study, researchers discovered a second receptor, called neuropilin-1, which may explain why the virus is so infectious.
This receptor is widespread in human tissues, they said, explaining that the new coronavirus has a convenient advantage when it infects human cells. All of these discoveries are critical in the race to develop a vaccine and treatment for Covid-19.
READ | Leading Covid-19 Vaccine Candidate 90% Effective in Phase 3 Trial
READ | The latest news on a leading Covid vaccine candidate is promising, but how optimistic should we be?
READ | Global experts cautiously welcome news about the efficacy of the leading Covid-19 vaccine candidate
Image: Getty / Andriy Onufriyenko
