Genomic characteristics of 2019 novel coronavirus in Suzhou City / 中华传染病杂志

ABSTRACT

Objective:To investigate the viral molecular mutations of 2019 novel coronavirus (2019-nCoV) and host adaptability in Suzhou City.Methods:The throat swab specimens from nine local cases and six imported cases with 2019-nCoV viral nucleic acid test positive in Suzhou City were sequenced for the whole genome of the virus, and the Wuhan-Hu-1 strain was used as the reference sequence for alignment and analysis. The phylogenetic tree of the viral whole genome sequence was constructed by MEGA 7.0 software.Results:According to the Chinese typing method, Nextstrain typing method, Pangolin classification method and Global Initiative on Sharing All Influenza Data (GISAID) typing method, the 15 2019-nCoV genome sequences could be divided into seven types, six types, eight types and five subtypes, respectively. Compared with Wuhan-Hu-1 strain, the median number of amino acid sequence mutation sites based on nucleotide translation was three (ranging from 0 to 12). D614G mutation of spike protein was identified from all six imported viral strains, which could enhance the transmissibility. No Alpha, Beta, or Gamma mutants, which also could enhance the transmissibility, was found in the genomic sequences of the imported cases. The median number of nucleotide mutation sites in 15 sequences was eight (ranging from three to 23).Conclusions:2019-nCoV is constantly mutating, and a variety of evolutionary lineages/genotypes have been derived. All imported viruses in Suzhou City carry mutations that can increase infectivity.