Number of SFPs in selected gene families. Of the available gene families in Additional File 1, Table S3.1, 13 are shown here that have been investigated in previous studies for comparison purposes. The observed number (black) of SFPs in a gene family is compared to the expected number (red) due to random chance. Gene families are sorted by the significance of the difference between observed and expected SFP numbers. All gene families show significantly different observed SFPs than expected except for RING genes (Additional File 1, Table S3.1). Deletions follow a similar pattern to SFPs by removing the most nucleotides from resistance, F-box and receptor-like kinase genes but differ by removing fewer nucleotides from cytoplasmic ribosomal genes. Duplications rarely occur in any of the chosen gene families. Although they do occur in resistance genes, the difference between observed and expected is not significant.