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  • ragowthaman
    Member
    • Nov 2009
    • 12

    Getting pileup consensus from BAM files using Bio::DB::Sam

    Hi List,
    I am trying to find out the consensus using pileup via Bio:B::Sam. Using the following script I could parse out the ref_base and different bases from reads at that position. Though, I am not able to find a method to derive consensus. Similar to the values produced by “samtools pileup –c –f xxxxxx.fasta yyyyyyy.bam”.

    The script I use now retrives ref base, query bases for each position. How do I improve it to get the consensus?

    Thanks very much in advance,
    Gowthaman


    use Bio:B::Sam;

    my $bam = Bio:B::Sam->new(-bam => 'something.bam’,
    -fasta => 'something.fasta'
    );

    my $cb = sub {
    my ($seqid, $pos, $pileups) = @_;
    my $refBase = $bam->segment($seqid, $pos, $pos)->dna;
    print "\n$pos\t$refBase=>";
    for my $pileup (@$pileups){
    my $al = $pileup->alignment;
    my $qBase = substr($al->qseq, $pileup->qpos, 1);
    print "$qBase,";
    }
    };

    $bam->pileup('Lin.chr10i', $cb);
  • lh3
    Senior Member
    • Feb 2008
    • 686

    #2
    There is no perl binding for samtools-like consensus calling.

    Comment

    • ragowthaman
      Member
      • Nov 2009
      • 12

      #3
      Oh! Thanks. I'll be good reading the pileup outfile then.

      Comment

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