Lecture notes on stochastic models in systems biology
  These notes provide a short, focused introduction to modelling stochastic gene expression, including a derivation of the master equation, the recovery of deterministic dynamics, birth-and-death processes, and Langevin theory. The notes were last updated around 2010 and written for lectures given at summer schools held at McGill University's Centre for Non-linear Dynamics in 2004, 2006, and 2008. 
Peter S Swain
q-bio.QM