The human disease network

Last year the New York Times published this article (http://tinyurl.com/69e388) about the human disease network. While the article focused mostly on how this work could affect the classification of diseases, this research has a couple unique characteristics. The nodes in the graph represent diseases, and two diseases are connected to each other if they share at least one gene implicated in both disorders. The graph has a scale-free structure, the phenomenon that certain nodes act as hubs instead of edges being homogeneously distributed. The significance of the scale free quality is that it can be used by researchers not only to investigate diseases with fewer implicated, but more importantly to predict what genes to potentially expect based on spatial proximity to other nodes on the graph.