The SARS-CoV-2 genome was found to possess 14 ORFs encoding 27 proteins. The orf1ab and orf1a genes are located at the 5′-terminus of the genome and encode 15 non-structural proteins (nsps) from nsp1 to nsp10, and from nsp12 to nsp16. The 3′-terminus of the genome contains 4 structural proteins (S, E, M and N) and 8 accessory proteins (3a, 3b, p6, 7a, 7b, 8b, 9b and orf14). At the amino acid level, the SARS-CoV-2 is quite similar to that of SARS-CoV, but there are some notable differences. For example, the 8a protein is present in SARS-CoV and absent in SARS-CoV-2; the 3b protein is 154 amino acids in SARS-CoV but shorter in SARS-CoV-2 with only 22 amino acids. Further studies are needed to characterize how these differences affect the functionality and pathogenesis of SARS-CoV-2 [95].