Emily
Editor, Senior Moderator
https://www.scientificamerican.com/article/why-is-monkeypox-evolving-so-fast/
Why is Monkeypox Evolving So Fast?
The virus circulating in the current outbreak has mutated 50 times in the past four years
Thus far, Neher wrote on Twitter, there is no indication that the mutations have helped the virus adapt to humans. In fact, most random mutations do nothing at all, so the new changes in the monkeypox genome may just be markers of human infection rather than the cause. Most of the mutations that Gomes’s team identified were small, although one gene had been deleted.
Orthopoxviruses seem to be able to survive a great deal of mutation. One study that analyzed smallpox in the skeletons of sixth-century Vikings found numerous genes that are inactivated in modern smallpox strains, suggesting that gene deletions are a normal part of how orthopoxviruses and host species adapt to one another.
That observation doesn’t mean mutations that help the monkeypox virus infect and spread in humans won’t appear in the future, says Geoffrey Smith, a virologist at the University of Cambridge. Several of the genes Gomes’s team identified occurred in proteins that interact with the human immune system, although there is no evidence that these strengthened the virus.
Roper isn’t so sure. “It’s my belief it mutated in some way early in this jump to become more transmissible in humans,” she says. Roper suspects that one of these fitter forms of the virus ended up in a so-called superspreader event. HIV followed a similar pattern: it jumped from animals into people several different times before becoming widespread. “This time [monkeypox] really got a foothold,” she says.
If mutations that helped the virus did appear, Smith says, scientists would be able to spot them. He and many others have spent decades studying the smallpox genome, whose central region is 96 percent identical to that of monkeypox. They know which proteins allow the virus to escape the immune system, for instance, or to spread more easily. “We know what to look for and haven’t seen it yet,” Smith says.
Still, Roper thinks it will likely be years before scientists can pinpoint which of the mutations that occurred are important and why. “These experiments are really hard to do,” she says. With SARS-CoV-2, for example, certain combinations of mutations seem to affect the virus’s ability to spread while other combinations do not...
Why is Monkeypox Evolving So Fast?
The virus circulating in the current outbreak has mutated 50 times in the past four years
- By Sara Reardon on July 20, 2022
Thus far, Neher wrote on Twitter, there is no indication that the mutations have helped the virus adapt to humans. In fact, most random mutations do nothing at all, so the new changes in the monkeypox genome may just be markers of human infection rather than the cause. Most of the mutations that Gomes’s team identified were small, although one gene had been deleted.
Orthopoxviruses seem to be able to survive a great deal of mutation. One study that analyzed smallpox in the skeletons of sixth-century Vikings found numerous genes that are inactivated in modern smallpox strains, suggesting that gene deletions are a normal part of how orthopoxviruses and host species adapt to one another.
That observation doesn’t mean mutations that help the monkeypox virus infect and spread in humans won’t appear in the future, says Geoffrey Smith, a virologist at the University of Cambridge. Several of the genes Gomes’s team identified occurred in proteins that interact with the human immune system, although there is no evidence that these strengthened the virus.
Roper isn’t so sure. “It’s my belief it mutated in some way early in this jump to become more transmissible in humans,” she says. Roper suspects that one of these fitter forms of the virus ended up in a so-called superspreader event. HIV followed a similar pattern: it jumped from animals into people several different times before becoming widespread. “This time [monkeypox] really got a foothold,” she says.
If mutations that helped the virus did appear, Smith says, scientists would be able to spot them. He and many others have spent decades studying the smallpox genome, whose central region is 96 percent identical to that of monkeypox. They know which proteins allow the virus to escape the immune system, for instance, or to spread more easily. “We know what to look for and haven’t seen it yet,” Smith says.
Still, Roper thinks it will likely be years before scientists can pinpoint which of the mutations that occurred are important and why. “These experiments are really hard to do,” she says. With SARS-CoV-2, for example, certain combinations of mutations seem to affect the virus’s ability to spread while other combinations do not...
