Documentation of any changes currently made SARS-CoV-2 According to a study led by researchers at University College London, the virus increases its transmissibility in humans.
Analysis of the virus genome of more than 46,000 people COVID-19 Published today (November 25, 2020) in 99 countries Nature Communications.
The first and corresponding author Dr. Lucy Van Derp (UCL Genetics Institute) said: “The number of SARS-Covey-2 genomes produced for scientific research is astonishing. We realized early in the epidemic that we needed new approaches to analyzing enormous amounts of data in real-time proximity to spread new mutations of the virus that could affect the severity of its transmission or symptom.
“Fortunately, we found that none of these mutations spread COVID-19 more rapidly, but we need to be vigilant and continue to monitor new mutations, especially as vaccines roll.”
There is a type of coronavirus like SARS-Covy-2 RNA Viruses, all of which can develop mutations in three different ways: by mimicking errors during viral replication, by interacting with other viruses that infect the same cell (reconstruct or restore), or by induced host RNA modification systems Part of which is the host immunity (e.g. the person’s own immune system).
Most mutations are neutral, while other viruses can be beneficial or harmful. Both neutral and beneficial mutations may become more common as they pass into the virus of the descending lineage.
UCL, CIRAD and University de la Reunion and research team Oxford University, Collected by the end of July 2020, analyzed a global dataset of the virus genome of 46,723 people with COVID-19.
Researchers have so far identified 12,706 mutations in SARS-COVID-2, the cause of the virus COVID-19. For 398 of the changes, there is evidence that they have occurred frequently and independently. Of these, the researchers paid homage to 185 mutations that occurred independently at least three times during the epidemic.
To test whether mutations increase the transmission of the virus, the researchers modeled the evolutionary tree of the virus, and analyzed whether an evolutionary evolution is growing normally in a given branch of the tree – testing whether the first evolution occurs after mutation. Why. One virus, the descendants of that virus, has surpassed the closely related SARS-Co-2 virus without that specific mutation.
Researchers have found no evidence that a common mutation is increasing the transmissibility of the virus. Instead, they found that most common mutations are neutral to the virus. It involves a mutation in a virus spike protein called D614G, which is said to be a mutation in general that can further infect the virus. New evidence has been found that this change is not in fact associated with a significantly increased transmission.
Researchers have found that most common mutations appear to be induced by the human immune system, as a result of the virus adapting to the human host of its novelty. This situation contradicts the second analysis done by the same team that happened when SARS-Covey-2 later went into minks that grew out of humans.
ड van. Van Dorpe said: “When we analyzed the virus genomes derived from mink, we were surprised to see the same mutation again and again in different mink farms, a mutation rarely seen in humans.”
Lead author Professor Francois Ballx (UCL Genetics Institute) added: “We will be able to pay for this period of early adaptation of the virus in humans. We previously estimated that Saras-Cove-2 would have jumped into humans in October or November 2019, but by the very end of December we have the first genome. By that time, critical viral changes for transmissibility in humans have emerged and become fixed, preventing us from studying it. “
The virus is expected to mutate and eventually turn into a different lineage as it becomes more common in the human population, but that does not mean that any lineage will come out that is more transmissible or harmful.
ड van. Van Dorpe said: “The virus seems to be well suited for transmission in humans, and by the time it became known as the novel virus, it has become the best in human host health.”
Researchers have warned that the imminent introduction of the vaccine is likely to bring new selective pressure on the virus to protect recognition by the human immune system. This can lead to the emergence of vaccine-escape mutants. The team stressed that the calculated structure they developed should prove useful for the timely identification of possible vaccine-escape mutations.
Professor Boulex concluded: “The news ahead of the vaccine sounds good. Viruses may well get vaccine-escape mutations in the future, but we are confident we will flag them immediately, which will allow vaccines to be updated in a timely manner if necessary. “
Ref: 25 November 2020, Nature Communications.
DOI: 10.1038 / s41467-020-19818-2
The study was supported by the Newton Fund UK-China NSFC initiative and the Biotechnology and Biological Science Research Council (BBSRC).
