Seqanswers Leaderboard Ad

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • biocomputer
    Member
    • Dec 2013
    • 62

    ChIP-seq analysis of repetitive sequences, should I remove (PCR) duplicates?

    When I do a normal alignment of paired-end ChIP-seq reads to the full mouse genome I identify PCR duplicates by looking for fragments that have identical coordinates and identical sequences for both forward and reverse reads. Now I'm looking for repetitive sequences by aligning to an index made up of all sequences from the UCSC RepeatMasker track. I'm not sure how or if I should be removing duplicates. It seems like repetitive sequences may be more likely align to the same positions and still be legitimate so I don't think a blanket removal of all these duplicates is the best option.

    I want to compare enrichment at repetitive sequences between multiple samples. Leaving in all duplicates may unfairly increase the magnitude of some changes between samples while removing them all may unfairly decrease some changes. For example, one particular repeat type is decreased in the treatment sample to 0.4 if I leave in duplicates and to 0.7 if I remove them. Maybe the true difference is somewhere in between there? In addition, in some cases the overall level of duplication between control and treatment samples is quite different (eg. 20% vs 30%) and it's hard to know if that's a real difference or not.

    Any ideas about what to do here?

Latest Articles

Collapse

  • seqadmin
    Pathogen Surveillance with Advanced Genomic Tools
    by seqadmin




    The COVID-19 pandemic highlighted the need for proactive pathogen surveillance systems. As ongoing threats like avian influenza and newly emerging infections continue to pose risks, researchers are working to improve how quickly and accurately pathogens can be identified and tracked. In a recent SEQanswers webinar, two experts discussed how next-generation sequencing (NGS) and machine learning are shaping efforts to monitor viral variation and trace the origins of infectious...
    03-24-2025, 11:48 AM
  • seqadmin
    New Genomics Tools and Methods Shared at AGBT 2025
    by seqadmin


    This year’s Advances in Genome Biology and Technology (AGBT) General Meeting commemorated the 25th anniversary of the event at its original venue on Marco Island, Florida. While this year’s event didn’t include high-profile musical performances, the industry announcements and cutting-edge research still drew the attention of leading scientists.

    The Headliner
    The biggest announcement was Roche stepping back into the sequencing platform market. In the years since...
    03-03-2025, 01:39 PM

ad_right_rmr

Collapse

News

Collapse

Topics Statistics Last Post
Started by seqadmin, 03-20-2025, 05:03 AM
0 responses
49 views
0 reactions
Last Post seqadmin  
Started by seqadmin, 03-19-2025, 07:27 AM
0 responses
57 views
0 reactions
Last Post seqadmin  
Started by seqadmin, 03-18-2025, 12:50 PM
0 responses
50 views
0 reactions
Last Post seqadmin  
Started by seqadmin, 03-03-2025, 01:15 PM
0 responses
201 views
0 reactions
Last Post seqadmin  
Working...