Seqanswers Leaderboard Ad

Collapse

Announcement

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

  • Newbie Q How to Mask MM9?

    The case is I'm analyzing murine tumor tissues (RNA-seq) on retroviral insertions. I have made a custom miltifasta genome, in which I have added the retroviral genome as an additional chromosome.

    When I map (BWA) I get an enormous background and many reads with mapping quality of zero because they map all around the murine chromosomes. Of course if one thinks about this, at least for the human genome an estimated 8-10% is of retroviral origin, hence background would be expected.

    Now, is it possible in some way to mask off the reference genome for endogenous retroviral sequences. Im a newbie in bioinformatics, but essentially what I want to do is copy-paste the retroviral genome and let som algorithm search in (perhaps) 20-40 bp frame windows across MM9 and replace regions with NNNs, that match my input retroviral sequence.

    Does anyone have some input on this? Or other considerations would be highly appriciated. Alternatively I could map against strain specific murien genome? Or transcriptome? But how to get this?

    TIA

  • #2
    I'm not sure you want to do that. If you hard mask them away, those reads will align somewhere sub-optimally, and you don't want that. You want those sequences mapping to the right place, you just want to know to ignore that place.

    You can always filter your .bam file to get rid of reads that have a mapping quality of 0.

    Comment

    Latest Articles

    Collapse

    • seqadmin
      Addressing Off-Target Effects in CRISPR Technologies
      by seqadmin






      The first FDA-approved CRISPR-based therapy marked the transition of therapeutic gene editing from a dream to reality1. CRISPR technologies have streamlined gene editing, and CRISPR screens have become an important approach for identifying genes involved in disease processes2. This technique introduces targeted mutations across numerous genes, enabling large-scale identification of gene functions, interactions, and pathways3. Identifying the full range...
      08-27-2024, 04:44 AM
    • seqadmin
      Selecting and Optimizing mRNA Library Preparations
      by seqadmin



      Sequencing mRNA provides a snapshot of cellular activity, allowing researchers to study the dynamics of cellular processes, compare gene expression across different tissue types, and gain insights into the mechanisms of complex diseases. “mRNA’s central role in the dogma of molecular biology makes it a logical and relevant focus for transcriptomic studies,” stated Sebastian Aguilar Pierlé, Ph.D., Application Development Lead at Inorevia. “One of the major hurdles for...
      08-07-2024, 12:11 PM

    ad_right_rmr

    Collapse

    News

    Collapse

    Topics Statistics Last Post
    Started by seqadmin, 08-27-2024, 04:40 AM
    0 responses
    16 views
    0 likes
    Last Post seqadmin  
    Started by seqadmin, 08-22-2024, 05:00 AM
    0 responses
    293 views
    0 likes
    Last Post seqadmin  
    Started by seqadmin, 08-21-2024, 10:49 AM
    0 responses
    135 views
    0 likes
    Last Post seqadmin  
    Started by seqadmin, 08-19-2024, 05:12 AM
    0 responses
    124 views
    0 likes
    Last Post seqadmin  
    Working...
    X