Unconfigured Ad

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • hrajasim
    Member
    • Aug 2009
    • 27

    #1

    Base qualities during qseq2fastq and export2sam conversion

    I started off with Illumina qseq format - converted to fastq.
    I used the sol2std conversion from Maq and used the fastq to align against reference using BWA.
    Used the original qseq files to align against reference using ELAND.
    I got the output of BWA in SAM format and ELAND in export (which I converted to SAM using export2sam.pl)
    Now, the purpose is to detect SNPs and indels using samtools which expects (or interprets) the base qualities in a particular phred scale (Phred+33 correct?).
    Could someone help me sort the out the base quality scales in these file formats and what is the correct way to format the input SAM files before running pileup?
    Same question for GATK unified caller - what kind of base qualities should I ensure is in the input SAM files?
    If I use a standard converter such as sol2std or export2sam how can I be sure the base qualities are in the correct scale?

    Thanks in advance.
    Last edited by hrajasim; 05-12-2011, 11:18 AM.
  • jeny
    Member
    • Mar 2010
    • 16

    #2
    I suggest you have a look to export2sam.pl script.
    In this file you could find a section "quality value conversion table" explaining quality format start point and end point.
    So you could know which quality format is used in result sam file, i.e. phred+33

    Hope this help.

    Comment

    Latest Articles

    Collapse

    • SEQadmin2
      16S/ITS Profiling vs. Shotgun Metagenomics: What Changes in Your Workflow?
      by SEQadmin2




      NGS has revolutionized clinical microbiology by offering new ways to identify and surveil pathogens without prior knowledge of the target. One popular approach is 16S rRNA and ITS amplicon sequencing, which targets specific microbial markers. But studies are increasingly incorporating shotgun metagenomics, a technique that sequences all DNA from a sample without targeting specific microbial markers. This approach allows more detailed taxonomic classification, detection...
      Yesterday, 06:46 AM
    • 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

    ad_right_rmr

    Collapse

    News

    Collapse

    Topics Statistics Last Post
    Started by SEQadmin2, 10-28-2026, 09:57 AM
    0 responses
    27 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 10-28-2026, 09:51 AM
    0 responses
    18 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 10-22-2026, 11:13 AM
    0 responses
    71 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 10-22-2026, 10:48 AM
    0 responses
    48 views
    0 reactions
    Last Post SEQadmin2  
    Working...