Frameshifting coding indels close together tend to compensate for each other. (a)An example of compensatory FS indels. The dog orthologue of human FLJ43860 contains two FS indels. Individually, they cause frameshifts, but together in-frame translation is restored. (b) Multiple FS indels within a window size were clustered, and their net change in size was calculated. On the y-axis is the fraction of clusters with indel net size divisible by three, where amino acids between the two FS indels would change, but ultimately in-frame translation is restored. Solid lines are used for multiple FS indels in coding exons; dashed lines are for intron regions.