Dendrogram analysis of human disease gene sets As archival information grows, analysis of complex molecular and genetic datasets using clustering or network approaches has become increasingly more useful [13, [42] [43] [44] [45] . Therefore, in addition to comparisons between individual diseases using human and mouse gene sets, we analyzed large gene groups using dendrogram and clustering approaches based on gene sharing between gene sets. Figure 2 shows a broad based dendrogram comparison based on gene sharing between 480 GAD disease gene sets, using gene sets each containing at least 3 genes. A striking feature of this analysis is that at a coarse level, major disease groups cluster together in space demonstrating shared genes between major clinically important disease groups. Disease domains are represented by groups such as cardiovascular disorders, metabolic disorders, cancer, immune and inflammatory disorders, vision, and chemical dependency. At finer detail within a specific broader group, it becomes clear that individual diseases with overlapping 