"On the Denaturation Transition of DNA"

David Mukamel, Weizmann Institute

When DNA molecules are  heated they undergo a denaturation
transition by which the two strands  of the molecule are separated
and become unbound. This phenomenon has been extensively studied
both theoreticall and experimentally since the sixties. Experimentally,
the denaturation transition is  found to be first order. However
all theoretical  models applied to this problem in the last four decates
yield a continuous transition.

A new  theoretical approach for studying this transition will be described.
It yields a first order transition, in agreement with experimental
observations.  Some  new predictions and experimental implications
of this approach will be discussed.