Derivation of transcript patterns by the AltTrans pipeline from AltSplice splice patterns. Each of the gene-transcript alignments from AltSplice is examined for the following: (i) the alignment shows a 3' dangling end on the EST/mRNA; (ii) such a dangling end shows a polyA tail sequence; and (iii) a polyA signal is seen on the gene within a maximum distance of 40 nts 5' to the cleavage position. Transcripts that show these features are grouped in a manner that each class of transcripts possesses the same exon/intron organisation and the same terminating polyA site. Such derived alternate transcript patterns are described as AltTrans transcript patterns. Note: Of the three EST's, that are all grouped under one AltSplice splice pattern, the EST3 does not show a "dangling end" and hence it is not considered further in the construction of AltTrans Transcript Patterns. EST1 and EST2 form two distinct transcript patterns that differ in terminating polyA sites.