We have recently conducted a selection pressure analysis on SARS-CoV-2 spike glycoprotein sequences. The analysis revealed not even a single site showing evidence of purifying selection but episodic diversifying selection on three sites. Out of these three sites, two sites are potentially relevant (Fig. 3).
Fig. 3 Structure of Spike Glycoprotein (PDB ID: 6VXX) of SARS-CoV-2. The detected residues under positive selection are shown in red color.
The analysis was performed using Hyphy  on the Datamonkey server . BUSTED , MEME , and FUBAR  methods were used. MEME  and FUBAR  found 3 and 5 sites respectively under positive selection. However, BUSTED  did not found any evidence of selection on the tested branches of the phylogeny.
These spike glycoproteins are being analyzed further. Additionally, we are analyzing spike glycoproteins of SARS-CoV for comparison between SARS-CoV and SARS-CoV-2 spike glycoproteins.
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