Abstract
It has been suggested by several authors that nonlinear excitations, in particular solitary waves, could play a fundamental functional role in the process of DNA transcription, effecting the opening of the double chain needed for RNA Polymerase to be able to copy the genetic code. Some models have been proposed to model the relevant DNA dynamics in terms of a reduced number of effective degrees of freedom. Here I discuss advantages and disadvantages of such an approach, and discuss in more detail one of the models, i.e. the one proposed by Yakushevich.