RESUMO
Global efforts are being taken to monitor the evolution of SARS-CoV-2, aiming at early identification of mutations with the potential of increasing viral infectivity or virulence. We report a striking increase in the frequency of recruitment of diverse substitutions at a critical residue (W152), positioned in the N-terminal domain (NTD) of the Spike protein, observed repeatedly across independent phylogenetic and geographical contexts. We investigate the impact these mutations might have on the evasion of neutralizing antibodies. Finally, we uncover that NTD is a region exhibiting particularly high frequency of mutation recruitments, suggesting an evolutionary path on which the virus maintains optimal efficiency of ACE2 binding combined with the flexibility facilitating the immune escape.
RESUMO
The emergence of comparative phylogeography requires tools that allow comparing quantitatively the genetic structures between species. Whereas numerous methods have been developed to compare trees inferred from two species, comparison methods involving population structures issued from Bayesian inferences or maximum likelihood criterion have been poorly investigated. Here, we present a method implemented in an r (CRAN) scripts collection, SIMIL, based on the mean absolute differences computed from structure 2 outputs. The scripts collection is illustrated by the computation of unweighted and weighted genetic-structure-similarity (GSS) indices in three alpine plants. Different weighting procedures - taking into account the level of overlap between the species sampling areas - are compared among the different species pairs and among the different numbers of gene pools considered in structure.
