Homology relationships among the four Zymoseptoria species including orthology (interspecies) and paralogy (intraspecies) were analyzed by a comparison of the predicted proteomes using the software package SiLiX (Miele et al. 2011). Of the total 44,227 proteins predicted in the four Zymoseptoria species, 39,177 (88.6%) were clustered into 10,612 families. These families belong to three categories. First, there are 10,361 families of orthologous sequences present in at least two species. The different distributions of these families across the Zymoseptoria species are shown in Figure 1. Second, there are 236 families of orthologous sequences that also included species-specific paralogous sequences, i.e., independent duplication of a conserved gene occurred in one or more species. Third, there are 15 families of paralogous sequences, i.e., duplication of species-specific genes. The remaining 5050 sequences that could not be classified into a gene family were considered as proteins encoded by orphan genes.