- Autores: Carla Maviana, Sergei Kosakovsky Pondc, Simone Marinia, Brittany Rife Magalisa, Anne-Mieke Vandammee, Simon Dellicoure, Samuel V. Scarpinoh, Charlotte Houldcrofti, Julian Villabona-Arenasj, Taylor K. Paisiea, Nıdia S. Trovaol Christina Boucherm, Yun Zhangn, Richard H. Scheuermannn, Olivier Gascuelq, Tommy Tsan-Yuk Lamr, Marc A. Suchards, Ana Abecasis, Eduan Wilkinsonv, Tulio de Oliveira, Ana I. Bentow, Heiko A. Schmidtx, Darren Martiny, James Hadfieldz, Nuno Fariaaa, Nathan D. Grubaughbb, Richard A. Nehercc, Guy Baelee, Philippe Lemeye, Tanja Stadlerdd, Jan Albertee, Keith A. Crandallff, Thomas Leitnergg, Alexandros Stamatakishh, Mattia Prosperia, Marco Salemia
- Ano de Publicação: 2020
- Journal: PNAS
- Link: https://www.pnas.org/content/early/2020/05/06/2007295117
There is obvious interest in gaining insights into the epidemiology and evolution of the virus that has recently emerged in humans as the cause of the coronavirus disease 2019 (COVID-19) pandemic. The recent paper by Forster et al. analyzed 160 severe acute respiratory syndrome coronavirus (SARS-CoV-2) full genomes available (https://www.gisaid.org/) in early March 2020. The central claim is the identification of three main SARS-CoV-2 types, named A, B, and C, circulating in different proportions among Europeans and Americans (types A and C) and East Asians (type B). According to a median-joining network analysis, variant A is proposed to be the ancestral type because it links to the sequence of a coronavirus from bats, used as an outgroup to trace the ancestral origin of the human strains. The authors further suggest that the “ancestral Wuhan B-type virus is immunologically or environmentally adapted to a large section of the East Asian population, and may need to mutate to overcome resistance outside East Asia.” There are several serious flaws with their findings and interpretation. First, and most obviously, the sequence identity between SARS-CoV-2 and the bat virus is only 96.2%, implying that these viral genomes (which are nearly 30,000 nucleotides long) differ by more than 1,000 mutations.