Chinese study: Novel coronavirus has evolved into two major subtypes
Updated 15:54, 07-Mar-2020
The novel coronavirus, which has caused the widespread epidemic COVID-19 since late December 2019, has evolved into two major subtypes, a Chinese study has revealed.
To detect whether the virus, named SARS-CoV-2, has mutated, a group of Chinese researchers conducted population genetic analyses of 103 publicly available genomes of the virus, and found that it had evolved into two major subtypes (designated L and S), with differentiated infectivity.
The understanding of different subtypes of SARS-CoV-2 will help promote differentiated and more efficient treatment of the disease. And the study also provides novel insights into tracing the intermediate natural host of SARS-CoV-2, according to the authors.
Below are the major findings of the study：
The S type was ancestral, and the L type evolved from S type.
The L type (about 70 percent) was more prevalent than the S type (about 30 percent).
Human intervention may have placed more severe selective pressure on the L type, which might be more aggressive and spread more quickly than the S type.
What remains unclear about the mutations ：
It is currently unclear whether L type evolved from the S type in humans or in the intermediate hosts.
It is also unclear whether the L type is more virulent than the S type.
Whether and how these mutations affect the transmission and pathogenesis of SARS-CoV-2 remain to be discovered.
Besides, the data examined in this study are still very limited, the authors wrote, adding that follow-up analyses of a larger set of data are needed to have a better understanding of the evolution and epidemiology of SARS-CoV-2.