  This paper presents a probabilistic approach for DNA sequence analysis. A DNA
sequence consists of an arrangement of the four nucleotides A, C, T and G and
different representation schemes are presented according to a probability
measure associated with them. There are different ways that probability can be
associated with the DNA sequence: one way is when the probability of an
occurrence of a letter does not depend on the previous one (termed as
unsuccessive probability) and in another scheme the probability of occurrence
of a letter depends on its previous letter (termed as successive probability).
Further, based on these probability measures graphical representations of the
schemes are also presented. Using the diagram probability measure one can
easily calculate an associated probability measure which can serve as a
parameter to check how close is a new sequence to already existing ones.
