Insertions and deletions (indels) in coding sequences can be highly disruptive, especially when they introduce frameshift mutations. We found that most small indels (98.74%) are in introns or intergenic regions, but 542 small deletions and 641 small insertions are in coding exons (Supplementary Fig. 2 and Supplementary Note 1). The small coding indels are enriched in trinucleotides, which account for 32% of small coding deletions and 38% of small coding insertions. Of the remaining coding indels, 45 are predicted to result in frameshift mutations through deletions (25) or insertions (20) (Supplementary Data 5).
