A new examination, carried out by an international team of researchers, demonstrated in both the laboratory and in animal models why the D614G variant was able to gain the upper hand over the wild-type SARS-CoV-2 virus.
The researchers claimed that their approach allowed them to characterize emerging mutations such as the British variant B.1.1.7 smoothly and swiftly.
The study, published in the journal Nature, stated that the D614G variant of coronavirus carries a mutation in the spike protein that makes it easier for the virus to cling onto human cells.
The increased replication of the D614G variant was also confirmed in vivo, in a new mouse model first described in this study. These experiments were also carried out at the IVI in Charaf Benarafa's group.
To compare the two variants, a mixture of equal parts of the original version of the SARS-CoV-2 virus and the D614G variant was applied to the nose of each animal (hamster) under light anesthesia.
The researchers induced the viruses on healthy sentinel animals of the same species, with six pairs of animals in total. The researchers found that in all sentinel animals, the proportion of transmitted SARS-CoV-2 viruses was massively dominated by the D614G variant early on.
The differentiation of the variants was carried out using the latest sequencing technology and PCR techniques by Martin Beer's team at the Friedrich Loeffler Institute.
The researchers believe that their study stands out because they were able to clearly discern the more efficient transmission of the mutated variant in direct comparison with the wild-type virus.
The researchers further mentioned that this approach can even be used to test any single mutation or a specific combination of mutations that are currently in circulation.