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  • PICARD reports only unmapped reads

    Dear all,

    I am new to the new gen seq and have a bit of a problem using PICARD.

    Basically, I have Illumina paired-end sequencing that was aligned with BWA and converted to sorted and indexed bam file with samtools. I am trying to collect some summary statistics on the number of mapped and unmapped reads, by using the CollectAlignmentSummaryMetrics in PICARD. PICARD reports the correct number of reads, but 0 for any of the metrics for aligned reads, i.e. all reads are unmapped.

    By looking at the sam file, I could see that a lot of the reads are mapped, e.g. bitwise flags of 147 and 99 for the pairs or 0x1+0x2+0x10+0x80 and 0x1+0x2+0x20+0x40, therefore no problems as far as I can see.
    Just cannot understand why PICARD reports that all reads are unmapped. Any help would be much appreciated.
    Last edited by saskak; 03-25-2011, 02:15 AM.

  • #2
    Managed to fix the issue to some extent.

    The same files + PICARD run OK on my Linux box (i.e. correct N of mapped reads), but my Solaris + PICARD reports 0 mapped reads. It seems some sort of java problem + the solaris machine.

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