Making sense of mutation: what D614G means for the COVID-19 pandemic remains unclear

[Mary Wilson]

Journal Pre-proof

Nathan D. Grubaugh, William P. Hanage, Angela L. Rasmussen

Abstract

Korber et al. (2020) found that a SARS-CoV-2 variant in the spike protein, D614G, rapidly became dominant around the world. While clinical and in vitro data suggest that D614G changes the virus phenotype, the impact of the mutation on transmission, disease, and vaccine and therapeutic development are largely unknown.

Introduction

...The new study by Korber et al. (2020) sits at the heart of this debate. They present compelling data that an amino acid change in the virus’ spike protein, D614G, emerged early during the pandemic, and viruses containing G614 are now dominant in many places around the world. The crucial questions are whether this is the result of natural selection, and what it means for the COVID-19 pandemic.

https://www.cell.com/cell/pdf/S0092-8674(20)30817-5.pdf

[JJackson]

Excellent, some common sense on S D614G rather than the usually ill informed media hype.

[JJackson]

I have made several very skeptical posts about the importance of the S D614G change which I viewed as of little importance based on the data at the time. This has not changed but there is a new preprint that gives some hints there may be something going on - but still only maybe. In brief it made no difference in the mouse model but became infectious earlier in hamsters. When grown in cell cultures of human epithelial cells taken from the upper, mid & lower epithelial track it grew better in upper and middle but the same in lower cells. When co-infected with both variants the G form out performed the D in cell culture. This paper is the first real data, I am aware of, that leads me think it may be a factor but in each case (apart from the hamster) the effects were fairly marginal. It is a long way from proving anything much about real world effects in humans but it does give some credibility for the hypothesis.
All of this is probably just of academic interest at this stage as the countries that started with D614G, in Europe and the Americas, are the main drivers of cases and spread leaving Singapore as the only country uploading D614 sequence data recently.
https://www.biorxiv.org/content/10.1...09.28.317685v1