Modelling Disorder: the Cases of Wetting and DNA Denaturation

TL;DR

This paper investigates how genetic sequence composition affects DNA melting temperature using solvable models, numerical simulations, and compares with experimental data, emphasizing the importance of disorder in modeling DNA denaturation.

Contribution

It introduces and solves new disordered models for DNA melting, demonstrating the significance of disorder and logarithmic corrections, and extends findings to more general models and experimental data.

Findings

Logarithmic corrections to critical temperature due to disorder apply broadly.

Disorder is a crucial factor in modeling DNA denaturation.

Theoretical results align well with experimental data.

Abstract

We study the effect of the composition of the genetic sequence on the melting temperature of double stranded DNA, using some simple analytically solvable models proposed in the framework of the wetting problem. We review previous work on disordered versions of these models and solve them when there were not preexistent solutions. We check the solutions with Monte Carlo simulations and transfer matrix numerical calculations. We present numerical evidence that suggests that the logarithmic corrections to the critical temperature due to disorder, previously found in RSOS models, apply more generally to ASOS and continuous models. The agreement between the theoretical models and experimental data shows that, in this context, disorder should be the crucial ingredient of any model while other aspects may be kept very simple, an approach that can be useful for a wider class of problems. Our work has also implications for the existence of correlations in DNA sequences.