Unconfigured Ad

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • a_mt
    Member
    • Jul 2012
    • 34

    #1

    bowtie2 output, sam to bam conversion error.

    Hi all,

    I am trying convert a sam file (PE bowtie2 default fr output) to bam file using samtools view command. But it's throwing the following error.

    Code:
    $ samtools view -bS -o aln3.bam aln3.sam
    [samopen] SAM header is present: 17 sequences
    [sam_read1] reference '451450' is recognized as '*'
    Parse error at line 2026299: sequence and quality are inconsistent
    When I looked at the partcular line,
    Code:
    sed -n 2026299p aln3.sam
            133     chr12   451450  0       *       =       451450  0       *       *       YT:Z:UP YF:Z:LN
    Its missing col1 (Qname) also CIGAR string, segment sequence and Quality scores are unavailable.

    When I checked for such lines
    Code:
    $ sed -n '/^[^H]/=' aln3.sam | wc -l
    5422
    There were 5422 lines.

    How do I proceed now?? Do I delete these 5422 lines from sam file?? This thread here had the same problem but it was with bwa aligner.


    Also my bowtie output after aligning says (many such lines are produced before showing final alignment stats):

    Code:
    Warning: skipping mate #2 of read '' because length (0) <= # seed mismatches (0)
    Warning: skipping mate #2 of read '' because it was < 2 characters long
    I am not able interprte this. Also my alignement stats says 99.97% pairs were aligned concordantly 0 times. I am bit amused.
    Code:
    1018542 reads; of these:
      1018542 (100.00%) were paired; of these:
        1018249 (99.97%) aligned concordantly 0 times
        188 (0.02%) aligned concordantly exactly 1 time
        105 (0.01%) aligned concordantly >1 times
    How do I proceed now??

    Thank you.

    Between I am new to analysis and I hope you people dont mind if my questions are too simple.
    Last edited by a_mt; 11-16-2012, 11:41 PM.
  • arcolombo698
    Senior Member
    • Nov 2013
    • 142

    #2
    Skipping Mate errors

    Hello. I have the same issue

    Warning: skipping mate #1 of read 'SN860:381:H80WNADXX:1:1101:18171:2118 1:N:0:1' because length (0) <= # seed mismatches (0)
    Warning: skipping mate #1 of read 'SN860:381:H80WNADXX:1:1101:18171:2118 1:N:0:1' because it was < 2 characters long

    Comment

    • Brian Bushnell
      Super Moderator
      • Jan 2014
      • 2709

      #3
      It sounds like you have a 0bp read, possibly due to quality trimming. You can try removing such reads (and their mates) with a tool that allows you to specify a minimum read length.

      Comment

      • gerbarinov
        Junior Member
        • Mar 2015
        • 3

        #4
        I solved this problem after trimming fastaq files with fastx_trimmer -f and fastx_trimmer -t operations with no 0bp read in output files. So the solution for me was to remove artifacts with fastx_artifacts_filter and then synchronize pairs with fastqCombinePairedEnd.py

        Comment

        Latest Articles

        Collapse

        • SEQadmin2
          Multiomic Liquid Biopsy: What DNA/RNA Panels Reveal That DNA Alone Can’t
          by SEQadmin2



          Tumors contain complex mixtures of cell populations that evolve in response to treatment and host-specific factors. Tissue biopsies provide only static snapshots of a tumor’s state. But what if we could follow that evolution over time using a minimally invasive technique?

          Liquid biopsies can detect tumor-derived material circulating in the bloodstream, providing a way to study treatment response, detect emerging resistance, and discover new biomarkers. Circulating
          ...
          10-14-2026, 09:55 AM
        • SEQadmin2
          New Genomics Technologies Take Aim at Long-Standing Limits
          by SEQadmin2


          Researchers using sequencing and genomics tools often have to make trade-offs. They can choose between speed or scale, short reads or long-range information, or targeted panels or a view of the whole transcriptome. New technologies that have been released this year are built to address those tough choices.

          We asked six companies the same four questions to learn about their latest products. The new technologies bring a lot to the table, including rethinking sequencing
          ...
          09-28-2026, 10:25 AM

        ad_right_rmr

        Collapse

        News

        Collapse

        Topics Statistics Last Post
        Started by SEQadmin2, 10-22-2026, 11:13 AM
        0 responses
        29 views
        0 reactions
        Last Post SEQadmin2  
        Started by SEQadmin2, 10-22-2026, 10:48 AM
        0 responses
        22 views
        0 reactions
        Last Post SEQadmin2  
        Started by SEQadmin2, 10-15-2026, 10:52 AM
        0 responses
        39 views
        0 reactions
        Last Post SEQadmin2  
        Started by SEQadmin2, 10-14-2026, 05:39 AM
        0 responses
        45 views
        0 reactions
        Last Post SEQadmin2  
        Working...