Multivariate Analyses of Codon Usage of SARS-CoV-2 and other betacoronaviruses

Haogao Gu; Daniel Chu; Malik Peiris; Leo L.M. Poon

ss frequent than the codons ending with adenine or thymine. This pattern of uneven usage 144 in synonymous codons is in accordance with the G + C content distribution results (codons 145 ending with guanine or cytosine were less frequently observed). 146 We found a substantial bias in amino acid usage among these four genes, and this bias is well 147 explained by the hydropathy of the encoded proteins (results from global correspondence 148 analysis on all the four genes, collectively, data not shown). The GRAVY scores for every 149 sequence were calculated to represent the degree of hydropathy. We discovered that the 150 . CC-BY-NC-ND 4.0 International license author/funder. It is made available under a The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.02.15.950568 doi: bioRxiv preprint nucleocapsid protein sequences had significantly lower GRAVY scores as compared to those 151 from other genes, while the membrane protein sequences had highest GRAVY scores (see 152 Supplementary Figure S3 ).