Statistical test for frequency of a given codon within a defined sequence

Hi guys, My question concerns making a statistical test regarding the frequency of occurrence of a triplet codon within a defined DNA sequence. For each triplet codon its frequency along an organism's complete genome is known. However, how can I now determine the likelihood of finding n codons of type x within a sequence of m DNA base pairs?

Sorry, this might be very bioinformatics focused...

Thanks, Simon

Answer 1

[Walter Roberson]

You should clarify whether you want to know the probably of "exactly n" or "at least n" or "at most n".

For calculation purposes it is important to know if codons can overlap, and to know whether they can occur starting on any boundary or only starting every 3 (e.g., if every position is part of some triplet codon and codons do not overlap then the calculation is different than if there can be non-codon "noise" of indefinite size between codons.)