Although there are still many unsolved mysteries for the new crown mutant strain "Omi Keron", through genetic sequence analysis, researchers found that the "Omi Keron" mutant strain may be caused by the new crown virus and another virus that causes the common cold. The combination of gene fragments has evolved.
So far, the majority of people infected with "Omi Keron" found in many countries around the world are still mildly ill. Analysis suggests that this may be related to the genetic characteristics of the "cold" virus carried by the virus.
An early study by nference, a data analysis company in Cambridge, Massachusetts, showed that cells in the lung and gastrointestinal system of patients can carry both the new coronavirus and the common cold coronavirus. This co-infection creates conditions for viral recombination. In this process, two different viruses in the same host cell interact and replicate at the same time to produce new copies of genetic genes from two different viruses, forming new virus mutations.
This latest research finding was first published on the OSF Preprints website on December 3. The researchers wrote that there are 26 amino acid mutations in the spike protein of the "Omi Keron" virus, including 23 substitutions, two deletions and one insertion. One of the insertion mutations ins214EPE has not been observed in any previous COVID-19 mutant strains. arrive. However, this mutant gene sequence is very common in viruses that cause the common cold (such as HCoV-229E) and is also present in the human genome.
Venky Soundararajan, a researcher at nference, who is in charge of the research, said that the same gene sequence has repeatedly appeared in a HCoV-229E coronavirus that causes the common cold in humans and a virus that causes immunodeficiency in people with AIDS.
The single-cell sequencing results also showed that the receptor ACE2 of the new coronavirus and the receptor ANPEP of the HCoV-229E coronavirus are co-expressed in the gastrointestinal tract (such as intestinal cells) and respiratory tissues (such as respiratory cilia cells). It is "reasonable" for the "Mikeron" to evolve in individuals infected with two viruses at the same time.
"Inserting specific gene fragments may make the Omi Keron virus look closer to humans, which will help it escape the human immune system," Soundararajan said. He believes that because this gene sequence is ubiquitous, it is very likely that "several generations" of viral gene recombination have occurred, and these recombinations have led to the emergence of "Omi Keron."
The researchers also said that this may mean that the virus is more likely to spread, but is more likely to cause mild or asymptomatic diseases. Although scientists are still unable to determine whether "Omi Keron" is more contagious than other variants, and whether it will cause more serious diseases, the cases of infection with "Omi Keron" variants found in many countries are still light. Symptoms are mostly.
Professor John Wherry, an immunologist at the University of Pennsylvania in the United States, said: “Generally speaking, when viruses accumulate a lot of mutations, they will lose part of their adaptability. Therefore, some mutations in the Omi Keron mutant strain may weaken the virus’s ability to replicate. Change some behaviors of the spike protein."
He believes that if the hypothesis that "Omi Keron" evolved from HIV patients is true, it means that the virus is becoming more and more adaptable to humans, rather than "eliminating the host."
However, the origin of the "Omi Keron" mutation needs more research to confirm. Other hypotheses suggest that the "Omi Keron" may have evolved in animal hosts for some time.
Researchers at nference believe that it is necessary to continuously sequence the genome of individuals co-infected with viruses, and develop a "mutation early warning system" as soon as possible based on the mutations that virus mutations are concerned about.
On the other hand, scientists are still confirming whether "Omi Keron" can win the competition with the "Delta" mutant. Although "Omi Keron" has dominated the recent COVID-19 infection in South Africa, in European countries such as the United Kingdom and France, "Delta" is still the mutant strain that currently poses the greatest threat.
However, according to a new forecast issued by the European Center for Disease Control and Prevention (ECDC), the "Omi Keron" variant is likely to become a popular variant in Europe in the next few months. "Preliminary data based on the model show that the new variant has a significant advantage over the delta variant that has so far dominated." ECDC reports, "but it still depends on the new variant compared to the past variant. The degree of this advantage and the degree of progress of the epidemic."
Sumit Chanda, a researcher in the Immunology and Microbiology Department of the Scripps Research Institute in the United States, said: “If the Omi Keron variant becomes an epidemic strain and only causes mild illness, it will The epidemic has brought a turnaround, which means that the new crown virus may become a seasonal virus like the flu."