There are two types of new coronaviruses. What does this mean?

  There was a piece of news that probably confused many people. On one side, scientists said that two new types of coronaviruses are currently spreading around the world; on the other side, the World Health Organization insists that “there is no evidence that the virus is changing.”
  So, how many new coronaviruses are there? Is this new discovery of scientists important to current prevention and control?
  Viruses are always mutating, especially RNA viruses like new coronaviruses (viruses whose genetic material is RNA, such as the famous HIV, Ebola, Spanish influenza, A H1N1 influenza virus, avian influenza virus, etc.) Belong to this category). When a person is infected by a coronavirus, it will replicate in large numbers in the respiratory tract and replicate the first generation. The first generation immediately begins to replicate the second generation, and the second generation replicates the third generation… so the virus reproduces geometrically The progression increases. Because duplication inevitably makes mistakes, about 6 genes will be mutated every time it is duplicated.
  Tang Xiaolu of Peking University in my country and his colleagues studied the viral genomes in about 100 cases, and they found two viruses: 72 were considered “L type” and 28 were classified as “S type”.
  Studies have also shown that the L-type is a mutation from the older S-type. When the virus jumped from animals to humans, it is very likely that only the first virus (ie S type), L type appeared soon after. Both are related to the current global epidemic. The current L-type virus is more common, which shows that it is “more aggressive” in spread than the S-type.
  The two identified strains have very little difference, and they are almost the same in terms of lethality. why? Because viruses want to harm us, they must use the proteins they make, and many genetic mutations do not affect protein production. There are two reasons for this result.
  The first case is that when a gene makes a protein, every 3 bases in the DNA or RNA chain correspond to one amino acid (the basic unit of the protein), but there are only 20 natural amino acids, so many combinations of bases Corresponds to an amino acid. In many cases, although the base is changed (that is, the gene is mutated), the amino acid produced can be unchanged.
  The second situation is that, like our human genes, there are many “junk genes” in the DNA or RNA of viruses. Junk genes are mutated just like normal genes, but they do not produce any protein. Their mutations will not have any effect on us.
  Therefore, although the new coronavirus has evolved two strains, although the L-type is more contagious than the S-type, because the L-type was the first large-scale epidemic, from the perspective of fait accompli, the WHO said, “There is no evidence “The virus is changing” is true and does not contradict the scientists’ conclusions. But if the virus continues to mutate and evolve into more infectious or more deadly strains than the L-type, the situation will really get worse.