Variants of SARS-CoV-2 have been identified rapidly after the beginning of pandemic. One of them, involving the spike protein PROTEIN
and called D614G, represents a substantial percentage of currently isolated strains. While research on this variant was ongoing worldwide, on December 20th 2020 the European Centre for Disease Prevention and Control reported a Threat Assessment Brief describing the emergence of a new variant of SARS-CoV-2, named B.1.1.7, harboring multiple mutations mostly affecting the Spike protein PROTEIN
. This viral variant has been recently associated with a rapid increase in COVID-19 MESHD
cases in South East England, with alarming implications for future virus transmission rates. Specifically, of the nine amino acid replacements that characterize the Spike in the emerging variant, four are found in the region between the Fusion Peptide and the RBD domain (namely the already known D614G, together with A570D, P681H, T716I), and one, N501Y, is found in the Spike Receptor Binding Domain - Receptor Binding Motif (RBD- RBM HGNC
). In this study, by using in silico biology, we provide evidence that these amino acid replacements have dramatic effects on the interactions between SARS-CoV-2 Spike PROTEIN SARS-CoV-2 Spike MESHD
and the host ACE2 receptor or HGNC
, the protease that induces the fusogenic activity of Spike. Mostly, we show that these effects are strongly dependent on ACE2 HGNC
polymorphism, suggesting that dynamics of pandemics are strongly influenced not only by virus variation but also by host genetic background.