throws NumberFormatException {
int exoncount = m2gSym.getChildCount();
int mrnalength = determinemRNALength(exoncount, m2gSym, genomic, exon_insert_list);
int end = 0;
String mrna_id = MRNASTR;
BioSeq mrna = new BioSeq(mrna_id, null, mrnalength);
mrna.setBounds(start, start+mrnalength);
mrna_hash.put(mrna_id, mrna);
SeqSpan mrna_span = new SimpleSeqSpan(mrna.getMin(), mrna.getMax(), mrna);
m2gSym.addSpan(mrna_span);
for (int i = 0; i < exoncount; i++) {
SimpleSymWithProps esym = (SimpleSymWithProps) m2gSym.getChild(i);
SeqSpan gspan = esym.getSpan(genomic);
end = start + gspan.getLength();