[greg5green]

The popular media has done a huge disservice by naming this the "Indian double mutant." It's two changes that have been seen in other variants and have been studied already.

The "double mutation" is L452R and E484Q. L452R is the defining feature of the B.1.429 variant (California). E484Q has been seen in derivatives of B.1.429 and in bunches of other variants in the US. It has some antibody evasive properties, but not enough to render vaccines ineffective. Yes, the E484K mutation seen in B.1.351, P.1, and P.2 has been more studied, but E484Q has been studied too.

Double mutant makes it sound like it is something entirely novel that is going to murder us all.

[raducu]

Isn't the fact that those two mutations pop up in Brazil, South Africa and now India a good thing?

That could mean it's likely the virus is running out of useful mutations?

[majewsky]

Yes. I've heard this argument being made by Christian Drosten (a German virologist specializing in coronaviruses) in his podcast a few months back.

[defaultname]

I assumed that the common mutations were the result of travel. Is that not the case? Is the belief that the virus is hitting the same mutations independently in multiple places?

[bart_spoon]

While its possible some of it is due to travel, I've definitely read that there is plenty of reason to believe these mutations are arising independently in different nations. Basically the virus is mutating all the time, but the vast majority of mutations are meaningless or have negative impact on the fitness of the virus. However some mutations may be more commonly observed, either because certain mutations in particular regions are more common (due to the physics/chemistry of the proteins involved) or because the mutation changes the virus in a way that makes it more like to stick and ultimately spread among the population. Some of these mutations are basically like local minimums in a mathematical function, and its not uncommon to see random traversals of that function coalesce around these minimums, at least temporarily.

[jb1991]

> this the "Indian double mutant."

I've actually seen it referenced as the "triple mutant"!