"we see no clear evidence of selection for stronger ACE2 binding, consistent with SARS-CoV-2 already possessing adequate ACE2 affinity at the beginning of the pandemic"https://www.biorxiv.org/content/10.1101/2020.06.17.157982v1 …
-
(2) Although a 97% identical RBD exists in another CoV, this doesn't explain the purifying selection and genetic stability of the circulating SARS2 RBD as early as Dec 2019.
That's a separate question. The lack of strong positive selection in the SARS2 spike is definitely of interest, but is it unusual? Sure, compared to SARS it is, but compared to other viruses? Not necessarily. In our paper we also consider potential 'pre'-circulation in humans.
-
-
Can you point out similar (RNA) viruses that do not have strong positive selection in their external proteins, and signs of purifying selection within weeks of emergence in humans? Agreed- we think pre-circulation in humans is possible as well and should be investigated.
-
Answering that question would require a broad formal analysis across multiple viruses, which I haven't done. Ebola (early) I have looked at previously, and there we get a dN/dS of ~0.5, while SARS2 (early) is ~0.3 and SARS1 (early) ~1.8.
- Nog 4 antwoorden
Nieuw gesprek -
-
Deze Tweet is niet beschikbaar.
-
Deze Tweet is niet beschikbaar.
Het laden lijkt wat langer te duren.
Twitter is mogelijk overbelast of ondervindt een tijdelijke onderbreking. Probeer het opnieuw of bekijk de Twitter-status voor meer informatie.