Figure 1.

Levels of alternative splicing in 16 human tissues with moderate or high EST sequence coverage. Horizontal bars show the average fraction of alternatively spliced (AS) genes of each splicing type (and estimated standard deviation) for random samplings of 20 ESTs per gene from each gene with ≥ 20 aligned EST sequences derived from a given human tissue. The different splicing types are schematically illustrated in each subplot. (a) Fraction of AS genes containing skipped exons, alternative 3' splice site exons (A3Es) or 5' splice site exons (A5Es), (b) fraction of AS genes containing skipped exons, (c) fraction of AS genes containing A3Es, (d) fraction of AS genes containing A5Es.