COVID-19 is a severe respiratory disease caused by the highly infectious SARS-CoV-2. As the COVID-19 pandemic continues, mutations of SARS-CoV-2 accumulate. These mutations may not only make the virus spread faster, but also render current vaccines less effective. In this study, we established reference sequence for each clade defined using the GISAID typing method. Homology analysis of each reference sequence confirmed a low mutation rate for SARS-CoV-2, with the latest clade GRY having the lowest homology with other clade (99.89%-99.93%), and the homology between other clade being greater than or equal to 99.95%. Variation analyses showed that the earliest genotypes S, V and G had 2, 3 and 3 characterizing mutations in the genome respectively. The G-derived cladesf GR, GH and GV had 5, 6 and 13 characterizing mutations in the genome respectively. A total of 28 characterizing mutations existed in the genome of the latest clades GRY. In addition, we found differences in the geographic distribution of different clades. G, GH and GR are popular in the USA, while GV and GRY are common in the UK. Our work may facilitate custom design of antiviral strategies depending on the molecular characteristics of SARS-CoV-2.

Fuente: Journal of Medical Virology

Published: 25 November 2021