Mutations that affect mRNA splicing often produce multiple mRNA isoforms containing different exon structures. Definition of an exon and its inclusion in mature mRNA relies on joint recognition of both acceptor and donor splice sites. The instant methodology predicts cryptic and exon skipping isoforms in mRNA produced by splicing mutations from the combined information contents and the distribution of the splice sites and other regulatory binding sites defining these exons. In its simplest form, the total information content of an exon, Ri,total, is the sum of the information contents of its corresponding acceptor and donor splice sites, adjusted for the self-information of the exon length. Differences between Ri,total values of mutant versus normal exons that are concordant with gene expression data demonstrate alterations in the structures and relative abundance of the mRNA transcripts resulting from these mutations.