Just a minor correction.
In article <1992Jul4.231658.6365 at ac.dal.ca>, arlin at ac.dal.ca writes...
>1. PAM stands simply for "percent accepted mutations" and not "point accepted
>mutations per 100 residues," as Gonnet and colleagues suggest (p. 1444, top
>left). I don't know where this interpretation started, but I've seen it many
>times before. Obviously, since "percent" is Latin for "per 100", both
>statements say exactly the same thing-- the only difference is that Dayhoff's
>original coinage conforms smoothly to the acronym "PAM," while the other
>coinage does not.
This is not what can be found in the "Atlas of Protein Sequence and
Structure" edited by M. Dayhoff. The definition of PAM is stated as a
"rearranged acronym for Accepted Point Mutations" and then described as a
measure of the number of individual amino acid changes occurring per 100
amino acid residues as a result of evolution.
This interpretation started because M. Dayhoff wrote these words, or
presumably at least edited these words.