Here’s a study on E. Coli. They force the bacteria to “mutate” to process glycerol. After six days, sure enough, a kinase shows up to handle the glycerol. But what is a “surprise” is that RNA polymerase shows up besides. It seems that two simultaneous mutations took place. But, of course, this is ONLY a surprise if you think RM+NS brought it about.
The authors say:
Mutations also appeared in a second, unrelated gene for an enzyme called RNA polymerase. “That was a surprise to almost everybody because RNA polymerase is involved in one of the core processes of any cell,” said Palsson. “You wouldn’t expect that gene to change because a wide variety of cellular process would be affected; it’s like replacing the wiring system in a building when a light bulb burns out. But we repeated the experiment more than 50 times and mutations in the RNA polymerase gene appeared again and again.”
I also enjoy the hesitation you almost hear as the reporter has to backtrack somewhat from RM+NS (listen for the word “presumably”):
All the mutants arose in the experiments presumably as the result of naturally occurring errors in copying DNA into daughter cells during cell division.
We here at UD have a better idea about what’s going on.
Here’s the link to the article.
By the way, some time back, in a heated debate over bacterial mutation and point mutations, I calculated that the amount of bacteria needed to provide TWO simultaneous point mutations simply through random chance would be so large that the known universe couldn’t contain it. I’m sure my calculation was off somewhere, but I think you get the picture: two genes being affected simultaneously is something that cannot happen by chance alone.