Just what we need.The following illustrates the problem with recombination. Recombination could allow the spike protein from SARS CoV 2 to wind up in Coronaviruses that currently only infect animals.
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bioRxiv - Extensive recombination-driven coronavirus diversification expands the pool of potential pandemic pathogens
Today, 07:24 AM
Extensive recombination-driven coronavirus diversification expands the pool of potential pandemic pathogens
Stephen A. Goldstein, View ORCID ProfileJoe Brown, Brent S. Pedersen, Aaron R. Quinlan, View ORCID ProfileNels C. Elde
doi: Extensive recombination-driven coronavirus diversification expands the pool of potential pandemic pathogens
This article is a preprint and has not been certified by peer review [what does this mean?].
Abstract
The ongoing SARS-CoV-2 pandemic is the third zoonotic coronavirus identified in the last twenty years. Previously, four other known coronaviruses moved from animal reservoirs into humans and now cause primarily mild-to-moderate respiratory disease. The emergence of these viruses likely involved a period of intense transmission before becoming endemic, highlighting the recurrent threat to human health posed by animal coronaviruses. Enzootic and epizootic coronaviruses of diverse lineages pose a significant threat to livestock, as most recently observed for virulent strains of porcine epidemic diarrhea virus (PEDV) and swine acute diarrhea-associated coronavirus (SADS-CoV). Unique to RNA viruses, coronaviruses encode a proofreading exonuclease (ExoN) that lowers point mutation rates to increase the viability of large RNA virus genomes, which comes with the cost of limiting virus adaptation via point mutation. This limitation can be overcome by high rates of recombination that facilitate rapid increases in genetic diversification. To compare dynamics of recombination between related sequences, we developed an open-source computational workflow (IDPlot) to measure nucleotide identity, locate recombination breakpoints, and infer phylogenetic relationships. We analyzed recombination dynamics among three groups of coronaviruses with impacts on livestock or human health: SARSr-CoV, Betacoronavirus-1, and SADSr-CoV.
We found that all three groups undergo recombination with highly diverged viruses, disrupting phylogenetic relationships and revealing contributions of unknown coronavirus lineages to the genetic diversity of established groups. Dynamic patterns of recombination impact inferences of relatedness between diverse coronaviruses and expand the genetic pool that may contribute to future zoonotic events. These results illustrate the limitations of current sampling approaches for anticipating zoonotic threats to human and animal health.
Competing Interest Statement
The authors have declared no competing interest.
https://www.biorxiv.org/content/10.1...02.03.429646v1
And apparently we're also assuming it was natural and not a lab virus.Previously, four other known coronaviruses moved from animal reservoirs into humans and now cause primarily mild-to-moderate respiratory disease.
Thanks for posting. It's interesting that he was personally so low given that he had been taking increased dosage.Dr. Campbell
Feb 11, 2021
Vitamin D, blood levels
Damn. It's been strangely quiet on the COVID front these past few weeks, relatively speaking. And now this. Almost as if the sky is ready to open up. Again.Recombination has finally reared its ugly head. I was afraid this was going to happen.
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Exclusive: Two variants have merged into heavily mutated coronavirus
Today, 02:13 PM
Source: https://www.newscientist.com/article...d-coronavirus/
Exclusive: Two variants have merged into heavily mutated coronavirus
The UK and California variants of coronavirus appear to have combined into a heavily mutated hybrid, sparking concern that we may be entering a new phase of the covid-19 pandemic
Health 16 February 2021
By Graham Lawton
Two variants of the SARS-CoV-2 coronavirus that causes covid-19 have combined their genomes to form a heavily mutated hybrid version of the virus. The “recombination” event was discovered in a virus sample in California, provoking warnings that we may be poised to enter a new phase of the pandemic.
The hybrid virus is the result of recombination of the highly transmissible B.1.1.7 variant discovered in the UK and the B.1.429 variant that originated in California and which may be responsible for a recent wave of cases in Los Angeles because it carries a mutation making it resistant to some antibodies.
The recombinant was discovered by Bette Korber at the Los Alamos National Laboratory in New Mexico, who told a meeting organised by the New York Academy of Sciences on 2 February that she had seen “pretty clear” evidence of it in her database of US viral genomes.
If confirmed, the recombinant would be the first to be detected in this pandemic. In December and January, two research groups independently reported that they hadn’t seen any evidence of recombination, even though it has long been expected as it is common in coronaviruses.
Unlike regular mutation, where changes accumulate one at a time, which is how variants such as B.1.1.7 arose, recombination can bring together multiple mutations in one go. Most of the time, these don’t confer any advantage to the virus, but occasionally they do.
Recombination can be of major evolutionary importance, according to François Balloux at University College London. It is considered by many to be how SARS-CoV-2 originated.
Recombination could lead to the emergence of new and even more dangerous variants, although it isn’t yet clear how much of a threat this first recombination event might pose.
Korber has only seen a single recombinant genome among thousands of sequences and it isn’t clear whether the virus is being transmitted from person to person or is just a one-off...