Unconfigured Ad

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • gongyh211
    Junior Member
    • Mar 2016
    • 3

    #1

    What's happening about my kmer spectrum? Heterozygous or repeats?

    I am doing a denovo genome sequencing and i get the kmer spectrum using clean reads of two paired end libarary data(see attach files). From the plot, i see high sequencing bias and two peaks, but i can not know whether the first peak(highest) is homozygous peak or heterozygous peak, the two situation are quite different. Whether the second peak (2X peak) is from large fragment duplication? or the first peak is heterozygous peak?
    Attached Files
  • westerman
    Rick Westerman
    • Jun 2008
    • 1104

    #2
    It is difficult to differentiate between zygosity effects and duplications. In part it depends on the type of organism you are sequencing. Plants are notorious for duplications but then it can be easy to breed them to be homozygous. So a bit more information would be appreciated.

    Comment

    • gongyh211
      Junior Member
      • Mar 2016
      • 3

      #3
      Originally posted by westerman View Post
      It is difficult to differentiate between zygosity effects and duplications. In part it depends on the type of organism you are sequencing. Plants are notorious for duplications but then it can be easy to breed them to be homozygous. So a bit more information would be appreciated.
      Thank you Westerman. What i am sequencing is a green algae probably diploid but we didnot have direct evidence.
      From the kmer spectrum, if the first mean peak is heterozygous peak, then it is so serious. I extracted the longest scaffold and two chloroplast scaffolds from the draft assembly, it shows 1.6%,2.1%,3.1% SNP (i use a simple ciritera: base coverage>=5 and highest nuc > 80%). It is very puzzled (chloroplast SNP>nuclear genome SNP?). One paper sequenced the chloroplast genome but very fragment(the author's explanation is repeats).
      Do you know why Dunaliella salina still not public one usable version from JGI? Our algae is near to Dunaliella salina from phylogenetic tree.

      Comment

      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
      43 views
      0 reactions
      Last Post SEQadmin2  
      Started by SEQadmin2, 10-22-2026, 10:48 AM
      0 responses
      33 views
      0 reactions
      Last Post SEQadmin2  
      Started by SEQadmin2, 10-15-2026, 10:52 AM
      0 responses
      44 views
      0 reactions
      Last Post SEQadmin2  
      Started by SEQadmin2, 10-14-2026, 05:39 AM
      0 responses
      45 views
      0 reactions
      Last Post SEQadmin2  
      Working...