[Bioperl-l] Bio::DB::GFF3 nightmare

[Marco Blanchette]

Dear all--

I have been trying to display exon/intron structure of mRNAs for a given
gene the D. melanogaster GadFly GFF3 annotation 4.2.1 loaded into mySQL
using bp_bulk_loadd_gff.pl. I keep getting  mRNAs from other genes that fall
within the segment of the queried gene. For example:

#!/usr/bin/perl
use strict;
use warnings;
use Bio::DB::GFF;

my $agg1 = Bio::DB::GFF::Aggregator->new(    -method => 'pre_mRNA',
                                            -sub_parts    =>
['exon','five_prime_UTR','three_prime_UTR'],
                                        );

my $dmdb = Bio::DB::GFF    ->new( -adaptor => 'dbi::mysql',
                          -dsn =>
'dbi:mysql:database=dmel_421;host=riolab.net',
                          -user => 'guest',
                          -aggregators=> [$agg1],
                );

my @genes = qw (CG17800);

for my $gene (@genes){
    my $tg = $dmdb->segment(-name => $gene);
    
    my @transcripts = $tg->features(-type => 'pre_mRNA',
                                     );
     
     for my $tc (@transcripts){
         my %atts = $tc->attributes;
         print "$_ => $atts{$_}\n" foreach (keys %atts);
     }
}

This script generate the output:
Parent => CG30501-RA
Name => Dscam:23
Parent => CG17800-RE
Parent => CG30500-RA
Name => Dscam:23
Parent => CG17800-RE
Name => Dscam:23
Parent => CG17800-RE
Name => Dscam:23
Parent => CG17800-RE
Name => Dscam:23
Parent => CG17800-RE

Where Neither CG30501-RA nor CG30500-RA are coming from the gene CG17800. If
I pass @transcripts to a Bio::Graphics::Panel object, I get, of course, all
the different mRNAs even the one that don¹t belong to the CG17800 gene.

I just can¹t figure out how to restrict the $tg->feature() call to the
queried gene (ie CG17800)

Many thanks
______________________________
Marco Blanchette, Ph.D.

mblanche at uclink.berkeley.edu

Donald C. Rio's lab
Department of Molecular and Cell Biology
16 Barker Hall
University of California
Berkeley, CA 94720-3204

Tel: (510) 642-1084
Cell: (510) 847-0996
Fax: (510) 642-6062
--