Fig. 1.

Mutations and the diversity of SARS-CoV-2. (a) The phylogenetic tree of SARS-CoV-2. Major variants are labelled on the graph, and the color of clans is according to the number of spike protein mutations. The tree is generated at https://nextstrain.org. (b) Mutation sites of the receptor binding domain. The residues below the red line are at or near the ACE2 binding interface. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)