Although similar CRK clusters are located in syntenic regions in other legumes, no putative ortholog to AeCRK could be found in M. truncatula or L. japonicus, and actually in no Papilionoid legume using a root hair- and infection thread-mediated infection process (Fig. 7f, Supplementary Fig. 24, and Supplementary Data 5). The gene discussed is CRK; the disease is infection.