No, you don't need mustations to 'add information' to the genes. All that has to happen is that there is a change in alleles over time.
That also include the removal of information. For example, man does not have the ability to synthsesis vitamin C on his own. Other primates do.
Cave dwelling species no longer have the ability to sense light. Their ancestors did.
As for the mathematics of it happening are.. just exactly how ARE you calcuating it? Are you taking into account that it is many tiny small steps, and not one big one?
I would say that the chance of SOMETHING happen chemically is 1.
Edited by ramoss, : No reason given.