The data on L. bicolor ABC genes were taken from our previous analysis [15]. All six species are engaged in ectomycorrhiza symbiosis with a wide range of forest trees, including both conifers and broad-leaved trees. The numbers of identified ABC genes in the genomes of mycorrhiza-forming Agaricales range from 33 genes in A. muscaria to 47 genes in C. glaucopus. All of the analysed species, except for H. cylindrosporum, are characterised by the presence of high numbers of gene fragments and putative pseudogenes related to the functional ABC protein-encoding genes, ranging from 15 in A. muscaria to 53 in L. amethystina (Additional file 1).