In this work we present a statistical model describing the denaturation process of DNA as a Markov process along the length of the chain. By identifying the stationary state of the Markov process with the equilibrium state of the system, we are able to obtain a relationship between the melting temperature and the fraction of base pairs of Cytosine–Guanine, [C+G] in the sequence. This relation is in close agreement with the experimental values reported by Marmur and Doty for long DNA chains of higher organisms in a biological range of temperatures. This model has two biological implications; on the one hand, it contributes to an understanding of the fundamental process of melting transition in DNA, and as a consequence, to have better conditions in the control of techniques such as polymerases chain reaction. On the other hand, this theoretical study could be an adequate framework to study the denaturation effects for long DNA and RNA chains at different physiological conditions.
