Researchers frequent concern with the separation between the computational modeling field and the development of theories is the starting point of this paper main claim that new Artificial Intelligence fields such as Artificial Life and Cellular Automaton can unite both areas (theory and model development), by defining data-led theory. To support this claim this paper stresses that it is possible to define a regional DNA1 through the use of CA models, and by doing so contribute to the development of theory. First the main historical phases of the computer model simulations in planning are presented. Second, the reasons why CAs are sensitive to local conditions and why that is very useful both as descriptive and prescriptive tool in planning (and in its tacit application) are detailed. Finally, it explores how the use of these calibration values can have another function by identifying keys/DNAs of each region. The use of two case studies points to the fact that it is indeed possible to define a regional DNA. Applications go beyond purely descriptive elements; they might have something to say in terms of data-led theories. Unlike past theories, they need to reflect an increasingly complex world, but keep with a simplicity that makes them very appealing.