def _get_intron_transcript_records(self):
if len(self.Exons) < 2:
self._set_null_values(["Introns"])
return
exon_positions = [(exon.Location.Start, exon.Location.End)
for exon in self.Exons]
exon_positions.sort()
end = exon_positions[-1][-1]
exon_map = Map(locations=exon_positions, parent_length=end)
intron_map = exon_map.shadow()
intron_positions = [(span.Start, span.End)
for span in intron_map.spans if span.Start != 0]
chrom = self.Location.CoordName
strand = self.Location.Strand
introns = []
rank = 1
if strand == -1:
intron_positions.reverse()
for s, e in intron_positions:
coord = self.genome.makeLocation(CoordName=chrom, Start=s, End=e,
Strand=strand, ensembl_coord=False)
introns.append(Intron(self.genome, self.db, rank, self.StableId,
coord))
rank += 1
self._cached['Introns'] = tuple(introns)
