passages.id: split_8_test_1793_passage
passages.type: progene_text
passages.text: Analysis of the genomic organization of SPEC1 revealed that the coding sequence of the SPEC1 isoform was derived from exons 2 , 3 and 4 , while the SPEC1-beta isoform was derived from exon 2 and a read - through event of intron 2 .