Unconfigured Ad

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • vcc
    Junior Member
    • Apr 2011
    • 4

    #1

    Bowtie output variability

    Hello everyone,

    I have used Bowtie many a times earlier, but was not trapped in such situation as given below:

    I have query related to bowtie output.
    1. When I am using bowtie with options (bowtie -a -p 32 <index> -1 reads1 -2 reads2 --phred33 -X 250 out.sam), I am getting the following output:
    # reads processed: 2357373
    # reads with at least one reported alignment: 1992781 (84.53%)
    # reads that failed to align: 364592 (15.47%)
    Reported 9698140 paired-end alignments to 1 output stream(s)

    2. and when I am using bowtie for same index and initial reads with options (bowtie -a -m 1 -p 32 <index> -1 reads1 -2 reads2 --phred33 -X 250 --al paired-all-ref.fastq --max paired-align-ref-max.fastq out.sam
    # reads processed: 2357373
    # reads with at least one reported alignment: 422462 (17.92%)
    # reads that failed to align: 1345003 (57.06%)
    # reads with alignments suppressed due to -m: 589908 (25.02%)
    Reported 422462 paired-end alignments to 1 output stream(s)

    From first and second you could see that there is high variation in aligned/unaligned total number of reads. Could anyone please guide me why this is happening.
    I need to extract paired end reads mapping more than one time. But these variations in output is confusing me.

    Also the reads length are 25 to 28 bases for each pair.
    Can I use Bowtie2, for such short reads.
    I also tried the the same with following options:
    bowtie2 -x <index> -q -1 reads1 -2 reads2 -p 32 --end-to-end --no-mixed --no-discordant -X 250 --no-unal -S out.sam
    and getting following output:
    2357373 reads; of these:
    2357373 (100.00%) were paired; of these:
    350824 (14.88%) aligned concordantly 0 times
    404316 (17.15%) aligned concordantly exactly 1 time
    1602233 (67.97%) aligned concordantly >1 times
    85.12% overall alignment rate

    It will be great if someone could help me out as soon as possible.

    Thanks

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
22 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 10-22-2026, 10:48 AM
0 responses
19 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 10-15-2026, 10:52 AM
0 responses
36 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 10-14-2026, 05:39 AM
0 responses
42 views
0 reactions
Last Post SEQadmin2  
Working...