Stepankiw N, Yang AWH, Hughes TR.

Genome Res. 2023 Nov 9. doi:10.1101/gr.277792.123

The human genome contains over a million autonomous exons.

“∼4.2 billion paired end reads [...] mapped to ∼6 million clusters [which] encompassed ∼9% of the genome.” “Internal exons from protein-coding genes [...] had an average of 10,636 reads, [...] encompassing 32% of all reads.” “exon clusters with at least 100 reads [captured] 1,245,947 exons in total, encompassing 3.2% of the stranded genome (i.e., 6.2 Gb)“. “5.3% of all intergenic region bases [...] are part of a trapped exon [424,632], corresponding to an exon every 3311 bases on average”. “52% of GENCODE lncRNA internal exons were trapped with at least 100 reads, a figure comparable to that of mRNA internal exons (61%).” “Known alternative cassette exons displayed, on average, 2.5-fold lower inclusion rates when compared to all internal mRNA exons.” “the trapped exons are very significantly depleted from introns, but not the mRNA antisense strand, and trapped exons that are detected in introns tend to have low read counts”