Unconfigured Ad

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • alpo
    Junior Member
    • Jul 2011
    • 1

    Crossbow alignment format

    I am using crossbow v1.1.1 on a local computer cluster to map a set of human SOLiD reads and call the variants. Crossbow glues together the bowtie aligner and SOAPsnp variant caller, and does this in a highly parallel fashion with an option to use the Amazon cloud.

    Currently, the program works well and the final SNP output is what is expected. However, I also need the alignment information from the initial bowtie alignment in BAM format, which crossbow does not currently support. Crossbow alignment output files can be retained and are in a 10-column tab-delimited format, but the format does not match standard bowtie output or SOAPsnp input. The following are four lines from the crossbow alignment file:

    19 0061 061971493 + TGAGTGAATTACATCATATCCACACAGATGAATGTATTACATCATATC `aXXc__^^_NR^[_`ac_^^ZMLZRTVSOLU?!<S8!+O?!6WS@1- 0 34:A>T 0 r
    16 0005 005054723 - GCATGTGTGTGTGTGTGTGTGTGTGTGTGTGTGTGTGGTGTGTGTGAG !!!!GHEFOM>17?ILDDB?BLUA579JRC3:G@JYYJLa_^__TQ]` 0 - 0 r
    2 0051 051640947 - TTGGCATCCCAAAGTGCTGGGATTACAGGCATGAGCCACCGTGCCTGG '/5L^;<]PE@@7AFDX][VZ^^ac`[UYbVV``ZZb`_ab_Y\__ba 0 - 0 r
    19 0055 055523009 + GTGAGCCGAGATCGCACCACTGCACTCCAGCCTGGGCGACAGAGTGAG ccccccccccbb_XZ]YUYab``ba[]aVTY[]QU_XZIBXacYW`aA 91 - 0 r


    Some of these columns are obvious and others are not (at least to me). From what I can gather the fields are:
    1: chromosome ID
    2: ??
    3: start position in reference
    4: strand orientation
    5: read bases
    6: quality string
    7: ??
    8: variant call (0-based)
    9: ??
    10: ?? It's always "r" ??

    My goal is write a script to turn this file into a SAM file and then use SAMtools for other analyses. Any help on this would be greatly appreciated. Thanks.
  • Ashwinub
    Junior Member
    • Sep 2013
    • 7

    #2
    Hello,

    Did you get a solution to this? I am wondering the same thing. Trying to analyze Crossbow alignment output.

    Thanks

    Comment

    Latest Articles

    Collapse

    • SEQadmin2
      Advanced Sequencing Platforms Tackle Neuroscience’s Toughest Genomics Problems
      by SEQadmin2



      Genomics studies in neuroscience face a special challenge due to the brain’s complexity and scarcity of samples. Mapping changes in cell type and state using conventional next-generation sequencing methods remains challenging. Advances in technologies like single-cell sequencing, spatial transcriptomics, and long-read sequencing have opened the door to deeper studies of the brain and diseases like Alzheimer’s, amyotrophic lateral sclerosis (ALS), and schizophrenia.
      ...
      07-09-2026, 11:10 AM
    • SEQadmin2
      Cancer Drug Resistance: The Lingering Barrier to Rising Survival
      by SEQadmin2



      Cancer survival rates have significantly increased in the last few decades in the United States, reaching a combined 70% 5-year survival rate by 2021. Behind this number, there are years of research to find new therapies, drug targets, and early detection methods. But there is one core challenge that keeps slowing down these advances, and it’s about drug resistance.

      There is no single reason why many patients don’t respond to treatment as expected. Cancer is...
      07-08-2026, 05:17 AM
    • GATTACAT
      Reply to Nine Things a Sample Prep Scientist Thinks About Before Sequencing
      by GATTACAT
      Love this - good data definitely starts from good input, and poor input can only give relatively poor data. I particularly like the mention of Nanodrop/absorbance based methods for quantification. It's such a toss up if you'll get an accurate reading or what amounts to a randomly generated number, and a lot of library/sequencing related issues can be traced back to poor quant.
      07-01-2026, 11:43 AM

    ad_right_rmr

    Collapse

    News

    Collapse

    Topics Statistics Last Post
    Started by SEQadmin2, Yesterday, 10:26 AM
    0 responses
    12 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 07-09-2026, 10:04 AM
    0 responses
    25 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 07-08-2026, 10:08 AM
    0 responses
    16 views
    0 reactions
    Last Post SEQadmin2  
    Started by SEQadmin2, 07-07-2026, 11:05 AM
    0 responses
    33 views
    0 reactions
    Last Post SEQadmin2  
    Working...