Seqanswers Leaderboard Ad

Collapse

Announcement

Collapse
No announcement yet.
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Bfast alignement with paired end reads in separate files

    Hello,

    I am dealing with Illumina paired end reads (100 + 100) and I am trying to align them by using bfast. The point is that they are in separate files, and I am wondering which is the best way to proceed. My attempt:

    1. bfast match:
    Code:
    bfast match -f hg19.fa -A 0  -g -r reads_file_pair_1.fastq.gz -i 1 -K 8 -M 128 -w 0 > pair_1.bmf
    bfast match -f hg19.fa -A 0  -g -r reads_file_pair_2.fastq.gz -i 1 -K 8 -M 128 -w 0 > pair_2.bmf
    2. bfast localalign:

    Code:
    bfast localalign -f hg19.fa -m pair_1.bmf -m pair_2.bmf -n 4 -A 0 -U > sample.baf
    3. bfast postprocess

    Code:
    bfast postprocess -i sample.baf -f hg19.fa -a 3 -z -A 0 -R -O 1 -n 4 -U | gzip > sample.sam.gz
    I am concerned specially in step 2; I am used to use two .bmf files (one per paired-end) in the bfast localign command when they have been outputted by the bfast bwaaln command (using "-1" and "-2" arguments), but I've never done so with bafst match output files.

    Tahnk you very much in advance,

  • #2
    Test it out to see what happens. You should be pleasantly surprised.

    Comment


    • #3
      Unfortunately, I think it does not work, the bfast localign seems to take into account only the second passed .bmf file:

      Code:
      bfast localalign -f hg19.fasta -m dummy_p1.bmf -m dummy_p2.bmf -n 4 -A 0 -U > dummy.baf
      The stdoutput when executing this command:
      Code:
      ************************************************************
      Printing Program Parameters:
      programMode:			[ExecuteProgram]
      fastaFileName:			hg19.fasta
      matchFileName:			dummy_p2.bmf
      matchFileNameOne:		[Not Using]
      matchFileNameTwo:		[Not Using]
      scoringMatrixFileName:		[Not Using]
      ungapped:			[Not Using]
      unconstrained:			[Using]
      space:				[NT Space]
      startReadNum:			1
      endReadNum:			2147483647
      offsetLength:			20
      maxNumMatches:			384
      avgMismatchQuality:		10
      numThreads:			4
      queueLength:			10000
      timing:				[Not Using]
      ************************************************************
      And effectively, I've checked the .sam file obtained after the bfast postprocess step and the aligned reads are only those of the second "end-reads" file.

      Am I doing something wrong? Btw, I am using the bfast+bwa-0.6.4e.

      Thanks,
      David

      Comment

      Latest Articles

      Collapse

      • seqadmin
        Essential Discoveries and Tools in Epitranscriptomics
        by seqadmin


        The field of epigenetics has traditionally concentrated more on DNA and how changes like methylation and phosphorylation of histones impact gene expression and regulation. However, our increased understanding of RNA modifications and their importance in cellular processes has led to a rise in epitranscriptomics research. “Epitranscriptomics brings together the concepts of epigenetics and gene expression,” explained Adrien Leger, PhD, Principal Research Scientist on Modified Bases...
        Yesterday, 07:01 AM
      • seqadmin
        Current Approaches to Protein Sequencing
        by seqadmin


        Proteins are often described as the workhorses of the cell, and identifying their sequences is key to understanding their role in biological processes and disease. Currently, the most common technique used to determine protein sequences is mass spectrometry. While still a valuable tool, mass spectrometry faces several limitations and requires a highly experienced scientist familiar with the equipment to operate it. Additionally, other proteomic methods, like affinity assays, are constrained...
        04-04-2024, 04:25 PM

      ad_right_rmr

      Collapse

      News

      Collapse

      Topics Statistics Last Post
      Started by seqadmin, 04-11-2024, 12:08 PM
      0 responses
      55 views
      0 likes
      Last Post seqadmin  
      Started by seqadmin, 04-10-2024, 10:19 PM
      0 responses
      52 views
      0 likes
      Last Post seqadmin  
      Started by seqadmin, 04-10-2024, 09:21 AM
      0 responses
      45 views
      0 likes
      Last Post seqadmin  
      Started by seqadmin, 04-04-2024, 09:00 AM
      0 responses
      55 views
      0 likes
      Last Post seqadmin  
      Working...
      X