evidence: Lu, R. et al. Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding. Lancet395, 565–574 (2020). [...] We gratefully acknowledge the submitting and the originating laboratories where genetic sequence data were generated and shared via NCBI and the GISAID Initiative. This work was supported by Grants from the National Key Research and Development Program (2019YFC1604600), the National Natural Science Foundation of China (31200941), the Fundamental Research Funds for the Central Universities (106112016CDJXY290002) and the National Natural Science Foundation of HeBei province (19226631D).