The presence of SFPs in various genomic structural features is shown as the number of SFPs per base pair for each entity. The spread of observed values across all accessions is shown in black. The blue band shows the range between the 1st and 3rd quartile while the red line shows the median value. A chi-squared test is used to determine whether the observed amount of SFPs per class was close to the expected number due to random chance. All classes are significantly greater than or less that random (p < 0.05) except for the classes 'intron', 'snRNA' and 'snoRNA'.