We also performed comparative genomic analyses of SARS-CoV-2 and SARS-CoV by zpicture. The results showed that the genomic sequences of SARS-CoV-2 and SARS-CoV have extremely high homology at the nucleotide level (Figure 4a,b). There are six regions of difference (RD) in the genome sequence between SARS-CoV and SARS-CoV-2, and the RDs are named according to the order of discovery. RD1, RD2, and RD3 (448nt, 55nt, and 278nt, respectively) are partial coding sequences of the orf lab gene; RD4 and RD5 (315nt and 80nt, respectively) are partial coding sequences of the S gene; RD6 is 214nt in size and is part of the coding sequence of the orf7b and orf8 genes. These RDs may provide new molecular markers for the identification of SARS-CoV-2 and SARS-CoV, and also help to develop new drugs against SARS-CoV-2.