Unconfigured Ad

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • aiden
    Junior Member
    • May 2010
    • 3

    #1

    Bfast output and "Empty Sequence Dictionary" in .sam output

    Hi there,
    I've recently been struggling with the .sam output file from BFAST postprocess. My goal is to get this output into a .ace format. Anthony Fejes recently tweaked the ConvertToAce utility within the Vancouver Short Read Analysis Package to accept .sam input files. However, when the utility runs I get an output like this:

    Code:
    Line 950
    Line: SRR026786.11209822        0       2010_05_14_New_Consensus_237-1  1130   255      23M4I9M *       0       0       TATCCACTGCACTCCACTCCACTGCCGCCGCTTCGT   IAIII;IFII+II>I)DAEI&>0+43$20*%2)*#"     PG:Z:bfast      AS:i:275        NM:i:9 NH:i:1   IH:i:1  HI:i:1  MD:Z:A7C14^GCCG1TA4A1   XA:i:3
    Ignoring SAM validation error due to lenient parsing:
    Error parsing text SAM file. Empty sequence dictionary.; File SRR026786_postprocess_nounmapped.sam;
    When I used the ValidateSamFile utility from Picard to check my .sam file, I get an error output saying that all of the lines have an empty sequence dictionary.

    The only processing that I've done to the .sam file between BFAST postprocess and the ConvertToAce utility is to remove unmapped reads using samtools view with the following options:

    Code:
    samtools view SRR026786_postprocess.sam -S -F 4 -o SRR026786_postprocess_nounmapped.sam
    ...Which makes me wonder why the Empty Sequence Dictionary error would occur unless there was some issue upstream in the work flow.

    Has anyone else had any issues with Empty Sequence Dictionary in BFAST postprocess .sam output files? Can anyone think of a work around? I know that Picard has the CreateSequenceDictionary utility, but I'm not sure how I could use this to add a sequence dictionary to each aligned read in my .sam file.

    Any ideas would be greatly appreciated.
    Aiden
  • nilshomer
    Nils Homer
    • Nov 2008
    • 1283

    #2
    Originally posted by aiden View Post
    Hi there,
    I've recently been struggling with the .sam output file from BFAST postprocess. My goal is to get this output into a .ace format. Anthony Fejes recently tweaked the ConvertToAce utility within the Vancouver Short Read Analysis Package to accept .sam input files. However, when the utility runs I get an output like this:

    Code:
    Line 950
    Line: SRR026786.11209822        0       2010_05_14_New_Consensus_237-1  1130   255      23M4I9M *       0       0       TATCCACTGCACTCCACTCCACTGCCGCCGCTTCGT   IAIII;IFII+II>I)DAEI&>0+43$20*%2)*#"     PG:Z:bfast      AS:i:275        NM:i:9 NH:i:1   IH:i:1  HI:i:1  MD:Z:A7C14^GCCG1TA4A1   XA:i:3
    Ignoring SAM validation error due to lenient parsing:
    Error parsing text SAM file. Empty sequence dictionary.; File SRR026786_postprocess_nounmapped.sam;
    When I used the ValidateSamFile utility from Picard to check my .sam file, I get an error output saying that all of the lines have an empty sequence dictionary.

    The only processing that I've done to the .sam file between BFAST postprocess and the ConvertToAce utility is to remove unmapped reads using samtools view with the following options:

    Code:
    samtools view SRR026786_postprocess.sam -S -F 4 -o SRR026786_postprocess_nounmapped.sam
    ...Which makes me wonder why the Empty Sequence Dictionary error would occur unless there was some issue upstream in the work flow.

    Has anyone else had any issues with Empty Sequence Dictionary in BFAST postprocess .sam output files? Can anyone think of a work around? I know that Picard has the CreateSequenceDictionary utility, but I'm not sure how I could use this to add a sequence dictionary to each aligned read in my .sam file.

    Any ideas would be greatly appreciated.
    Aiden
    Use the "-h" option with samtools view, otherwise the SAM header (with the sequence dictionary) will not be outputted by "samtools view".

    Comment

    Latest Articles

    Collapse

    • SEQadmin2
      Beyond CRISPR/Cas9: Understand, Choose, and Use the Right Genome Editing Tool
      by SEQadmin2



      CRISPR/Cas9 sparked the gene editing revolution for both research and therapeutics.1 But this system still showed severe issues that limited its applications. The most prominent were the heavy reliance on PAM sequences, delivery limitations, double-stranded breaks that prompt unintended edits and cell death, and editing inefficiency (both in targeting and in knock-in reliability).

      Despite this, “CRISPR helped turn genome editing from a specialized technique into
      ...
      07-31-2026, 11:01 AM
    • SEQadmin2
      Proteomic Platforms: How to Choose the Right Analytical Strategy to Improve Detection and Clinical Applications
      by SEQadmin2


      Proteomics platforms are evolving rapidly, with advances in mass spectrometry and affinity-based approaches expanding what researchers can detect and at what scale. As the field moves toward deeper proteome coverage and clinical applications, scientists face an increasingly complex landscape of tools. This article will explore how researchers are navigating these choices to find the right platform for their work.

      The systematic characterization of the human proteome has
      ...
      07-20-2026, 11:48 AM

    ad_right_rmr

    Collapse

    News

    Collapse

    Topics Statistics Last Post
    Started by SEQadmin2, 08-06-2026, 07:41 AM
    0 responses
    16 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 08-03-2026, 10:13 AM
    0 responses
    32 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 07-31-2026, 02:55 AM
    0 responses
    42 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 07-24-2026, 12:17 PM
    0 responses
    26 views
    0 reactions
    Last Post SEQadmin2  
    Working...