Although this is a random event, a variant has now been born. It happens constantly. Fortunately, most of these accidents have no effect on the infection, spread or severity of the disease and go away quickly. The most useful, however, those that help the virus replicate faster, create champions that can replace previous variants. These are called a strain.
Some virologists believe that SARS-CoV-2 arose during the encounter between a horseshoe bat and a so-called “reservoir” host (such as a pangolin) over a year ago. Others believe the virus had already circulated quietly in animals and humans long before it mutated into the form that took off at the end of 2019. Either way, the virus that causes COVID-19 mutated for a year now.
A new article by a team of doctoral students from the School of Information Sciences at the University of Illinois plotted the rate of mutation in the 29 proteins that make up SARS-CoV-2. These details are important because if a protein mutates a lot, it experiences high levels of entropy – it is indeed a moving target, and it is bad for vaccines.
The good news, the authors report, is that some of their findings offer hope for vaccines now on the market – at least initially. The bad news, they add, is that there are multiple “regions of intrinsic disorder” on the protein structure of the virus, which could lead to problems for these vaccines over time.
But at least the manufacturers of future vaccines will know how to target these regions afterwards.
“The history of advanced proteins is a good result,” says lead author Gustavo Caetano-Anolles. Here he talks about the document’s discovery that mutations in the SARS-CoV-2 spike protein have slowed down over the past year, with the protruding peak of all coronaviruses having now become a familiar presence in our lives. .
As the landing gear was expected to lock SARS-CoV-2 to ACE2 receptors in the lungs, COVID-19 spikes will soon become the target of two COVID-19 vaccines that are expected to receive approval first. The Pfizer and Moderna products use mRNA – a synthesized set of genetic instructions that direct the body to produce a surplus of floating spikes, preparing the immune system to pursue them when they finally arrive attached to SARS-CoV-2.
Like others before them, the Caetano-Anolles team has learned that the protein controlling the peak (it’s called G614D) has become less mutable over the past year. This means that the vaccines that will be shipping soon have been designed to take something that won’t change much. “This tells you that the peak mutation is becoming stable and that if you target the peak, it’s not a protein that will go away in a few months. That’s good news.” The bad news, he says, is that they have also identified 27 amino acids out of the 29 proteins in the virus as places that are still changing a lot.
“These are all ways the virus will need to avoid being targeted by any vaccines we may generate.”
You see, in addition to copying errors, viruses mutate after hitting roadblocks, and new vaccines will create a barrier to function when the spike protein is attacked. While it may sound like an Achilles heel crucial to the survival of COVID-19, “the S protein is just one entry point among the many things that happen with the infection process,” says -he. “Without it, the virus titer will decrease, but the virus will continue to infect.”
If anything, the lesson from the ongoing mutation of COVID-19, a story now writing its second and third chapters, maybe we’ll be lucky if our vaccines provide us with a bridge to normalcy until the next mutation that matters.
In this sense, the end goal of genetic monitoring for COVID-19 is not so much to eradicate the virus, but to stay on top of changes long enough for the body to bring it back to something more manageable.
“Some coronaviruses live with us and don’t cause disease,” says Caetano-Anolles. “This is the best option for the virus … He wants to strike a balance between very aggressive and very gentle. This thing came from animals, so it’s a weirdness, and tries to strike that balance.”
Caetano-Anolles is reluctant to predict how long it might take. We have, he said, opened Pandora’s box.
Viruses are part of the cycle of life. Like cancer, they are products of mutation, something that presumably promotes adaptation, diversity and survival. This suggests that we will find a path to coexistence with SARS-CoV-2.
“Humans, animals and all organisms have lived with viruses for a long time … this pandemic only underscores that,” he says.
These are pretty important topics for a team of graduate students.
“We were fortunate,” he says, “to ask some interesting questions about how the virus is evolving in the first wave that crossed the world. Now we need to ask ourselves these second and third wave questions.