In one of Monthy Python’s series there was this animated cartoon (by Terry Gillian) about the eminent yellow danger, world wide communist conspiracy that finally causes dental canker and severe tooth loss in people of the free, western countries. To combat this threat, all people in the free western world should therefor use the new toothpaste “Crelm”, making the teeth resistant against the communist conspiracy. This was really a fine irony about the hypocrisies of the commercial advertisement business.
Today I was reminded to this crazy Monthy Python sketch, when a colleague of mine from the Cambridge Sanger Center gave a talk about stem cells and their role in cancer progression. In his talk I heard for the first time about a new kind of mutation in the p53 gene, called the communist mutation. What this should be ?  Is this a mutation that causes a disorganization of tissue architecture ?  Or will people who carry the communist p53 mutation develop persistent revolutionary ambitions ? Or maybe cells which acquire this communist mutation turn red, like those transfected with a red-fluorescence protein ?  So I asked the scientist during the next coffee break what characterizes a communist p53 mutation, if there are also capitalist ones and – if yes – which of the two are more dangeous.
communist mutation
First he did not understood my point, but than he started laughing and excused for his North-English accent. He said that he meant that this mutation is the “commonest” of all the mutations in this gene. But then, shouldn’t this correctly be called “the most common mutation” ?
I never expected that I have to suggest a proper English grammar to an Englishman from one of the famous red-brick (hic!) Cambridge / Oxford colleges.
The fact that I mixed “commonest” and “communist” is not simply by mishearing. The two words share the same etymological origin. They are both derived from the latin word “Comoine”, meaning shared things. This can be tracked further to the Proto-Indo-European word *ko-moin-i. It was only in the English language that “common” became synonym with “frequent”, by the assumption that something that is shared by many (i.e. common) intuitively has also to be frequent. I have some objection to this line of argument. A subway train is perhaps the most common transport vehicle in big cities such as London, Moskow or Berlin, because a single train is shared by many passengers (i.e. its is common). But it is by fare not the most frequent type of vehicle. Taxis or private cars are by far more frequent, despite they are not common (because they are rarely shared).

Here is the original Monthy Pythons sketch: