Variables: The virus lacks creativity | Science | News | the sun

aN particularly speaks of the British (B.1.1.7), South African (B.1.351) and Brazilian (P.1) variants: these are the so-called “disturbing” variants (in English, Variables of concern). But there are many other species that are less “of concern” or “variants of interest” – for example, their transmission rate does not appear to be higher than the transmission rate of the original strain. Evolutionary microbiologist von Cooper wrote on the journal’s website that they had more in common than abundance indicated. Scientific American. Studies on which have been performed identify the signatures of what biologists call “evolutionary convergence”.

This is what happens in animals when the same trait appears in more than one species independently. The same adaptation, but that does not come from a common ancestor. Biologists often give as an example the fins of sharks and sea turtles, but these two species have been inherited from different ancestors.

A special mutation

A similar phenomenon is in SARS-COV-2 variants. We already knew that, like all viruses, it evolves, which means it undergoes mutations. In recent months, some of these mutations have been known to make some “variants” more transmissible than others – and possibly more vaccine-resistant. But it turns out that those previously thought to be differentiated mutations are not: In our laboratory at the University of Pittsburgh alone, Vaughn Cooper explains, seven genetically independent lines have been identified that acquired the mutation in one location. [Spike ou “épine”] The virus that it uses to enter the human cell. “

This particular mutation relates to an amino acid. We do not know the reason, but the fact that it occurs in the “region” of the protein known as the “thorn” that penetrates the human cell, cannot be a coincidence.

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And this is not the only example of convergent evolution. The example that is attracting the most interest among experts around the world is the set of mutations distributed in at least eight sites of protein S, observed in so-called British and South African variants. The Brazilian, as well as their lesser-known cousin p3, is one of these mutations, called E484K, that allows the virus to escape from human antibodies.

What all this means is that behind the apparent mess these multiplying variants create, there may be a small set of “prescriptions” or mutations that repeat from one strain to the next – and identifying them is likely to prevent vaccines from becoming less effective and less effective.

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