Has the new coronavirus mutated? How do I mutate? This is one of the focuses of academic research at present. The latest findings by a Chinese research team show that the new coronavirus has recently produced 149 mutation points and evolved two subtypes, L subtype and S subtype respectively. The study found that the two subtypes showed significant differences in geographical distribution and proportion of the population.
(Original title: Chinese scientific research team: the new coronavirus has mutated, there are 2 subtypes, there are differences in infectious power)
The Model S is a relatively old version, while the L sub type is more aggressive and contagious. A deep understanding of the different subtypes will contribute to the differential treatment and prevention and control of new coronary pneumonia.
The study comes from a march 3 paper published in the National Science Review, sponsored by the Chinese Academy of Sciences, on the origin and continuous evolution of SARS-CoV-2 evolution of SARS-CoV-2).
The paper is written by Lu Jian Researcher (Institute of Biological Information, School of Life Sciences, Peking University) and Cui Jie (Shanghai Pasteur Institute, Chinese Academy of Sciences).
By analyzing the evolution of the 103 new coronavirus whole genome symbits to date, the paper found that 149 mutation points have occurred in the strain, most of which have recently occurred. The study revealed that the new coronavirus has evolved into two subtypes, L and S. Of these, 101 belong to these two subtypes. In terms of proportion, the L subtype is more common to reach 70%, S subtype accounted for 30%.
According to the authors, according to the evolution of the new coronavirus, there may be a big difference in the propagation ability and the severity of the L subtype and the S subtype.
The paper says that the difference between the two subtypes is the 28144th point of the viral RNA genome, the L subtype is T base (for leucine, Leu), and the S subtype is C base (corresponding to ser). By comparing it with other coronaviruses, the authors found that the new s-type coronavirus was closer to the bat-sourced coronavirus in the evolutionary tree, leading to the conclusion that Type S is relatively old.
The L subtype is more common in the early stages of the outbreak in Wuhan, while the frequency of the L subtype has decreased since the beginning of January 2020. The authors argue that human intervention may exert greater selective pressure on the L subtype, without which the L subtype may be more aggressive and spread more quickly. On the other hand, because of the relatively weak selection pressure, the older and less aggressive S-type may increase in relative frequency. These findings mean that there is an urgent need for further comprehensive research in the context of genomic data, epidemiological data and the 2019 coronavirus disease patients’ clinical symptoms charted.
In addition, it is worth noting that the 103 samples showed that the majority of patients were infected with only one of the L or S subtypes. But one of the U.S. patients with a recent history of travel in Wuhan isolated a strain of the virus, both sites show a mixture of C and T, that is, it is likely that the patient was infected with both L-type and S-type new coronavirus. However, the authors say it is not possible to rule out a new variant.