// after a 3' has been inserted ill mess up coordinates of 3'.
// assuming for now that exon inserts are ordered in the XML
// sorting exons, so that later position calculations are accurate
Collections.sort(exon_list, new SeqSymStartComparator( genomic, forward));
for (SeqSymmetry esym : exon_list) {
m2gSym.addChild(esym);
}
BioSeq mrna = addSpans(m2gSym, genomic, exon_insert_list, start);