How are Genetic Circuits Modelled?
The following papers are a good starting point:


René Thomas, Boolean formalization of genetic control circuits, Journal of Theoretical Biology, Volume 42, Issue 3, December 1973, Pages 563-585 &lt;= A classic paper in the field. 
Thieffry D. Dynamical roles of biological regulatory circuits. Brief
Bioinform. 2007 Jul;8(4):220-5. 
Remy E, Ruet P. From minimal signed circuits to the dynamics of Boolean
regulatory networks. Bioinformatics. 2008 Aug 15;24(16):i220-6


You can also have a look at Computational Methods in Systems Biology, International Conference CMSB 2007, Edinburgh, Scotland, September 20-21, 2007. Proceedings, specifically the chapter "Decision diagrams for the representation and analysis of logical models of genetic networks" by A. Naldi, D. Thieffry and C. Chaouiya,