Modelling the deoxyribonucleic acid (DNA) dynamics and understanding the action of all the various factors involved remain the major challenge in Nonlinear Physics, biology and even in chemistry. This vivid interest arises of course not only from the biological relevance of DNA but also from its physical properties which can now be probed through single-molecule micromanipulation experiments. It is no more to be demonstrated that nonlinear distortions could play a major role in DNA functions, where nonlinear interactions can give rise to very stable excitations, called solitons, capable of ...