Table 3.

Localization of Splice Variations: Statistics

	Constitutive exons							Cryptic internal exons
Splice site usage	5′-UTR	CDS	3′-UTR	?^a	5′-UTR	CDS	3′-UTR	?^a	5′-UTR	CDS	3′-UTR	?^a
Invariant	4046	36,540	2531	2990	453	2632	114	324	802	1487	140	350
Alternative 5′	285	768	55	129	9	51	5	5	40	42	2	6
Alternative 3′	211	1,104	74	133	19	73	5	9	0	44	9	3
Alternative 5′ and 3′	2	17	4	10	1	7	0	1	1	0	0	1

Impact of Alternative Initiation, Splicing, and Termination on the Diversity of the mRNA Transcripts Encoded by the Mouse Transcriptome