Unconfigured Ad

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • wei210
    Junior Member
    • Jul 2019
    • 4

    am I overclustered -- MiSeq

    Hello, hope everybody had a good weekend so far. Sorry, I had a naive question and would appreciated it for any help.

    I run a PE V2 run for MiSeq (cancer custom lib with Illlumina P7/P5 primer).
    My target cluster density 1000-1200k, and I got 1328k, PF 95% and Q30 93%.

    Although most of the Thumbnails seems OK (like #1), i did see lots of Thumbnails like #2 and #3 below. Will #2 suggest overclustered and #3 not focused Thumbnails? also, I could not explain why the base C has significant higher density than others (please see picture below) while I think my sample of high diversity. Am I overclusterd? Any explanation to help me understood these will be much appreciated.

    Thanks
    Wei210
    Attached Files
  • nucacidhunter
    Jafar Jabbari
    • Jan 2013
    • 1250

    #2
    Cluster density is above specification but final results for PF and Q30 looks good. Those thumbnails are specific for selected cycle and base and if you select different base at the same cycle it will look different depending on frequency. Intensity plot also indicates that library is not as balanced as thought. If you select %base from drop down menu in that plot it will give good indication of base frequency at each cycle.

    Comment

    • wei210
      Junior Member
      • Jul 2019
      • 4

      #3
      Thank you so much, that helps lot.

      Comment

      Latest Articles

      Collapse

      • 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
      • SEQadmin2
        Nine Things a Sample Prep Scientist Thinks About Before Sequencing
        by SEQadmin2


        I’m not a sequencing expert. I’m a purification scientist who uses NGS to evaluate workflows my group develops. With this perspective, we think about the sample first and the NGS workflow second. The sequencer is an exceptionally honest reporter, but it can only report on what you give it, so whether you get clean, interpretable data from an NGS workflow is largely determined before you begin.

        Here are nine questions we think about, in roughly the order they matter, before...
        06-18-2026, 07:11 AM

      ad_right_rmr

      Collapse

      News

      Collapse

      Topics Statistics Last Post
      Started by SEQadmin2, Yesterday, 11:08 AM
      0 responses
      6 views
      0 reactions
      Last Post SEQadmin2  
      Started by SEQadmin2, 06-30-2026, 05:37 AM
      0 responses
      11 views
      0 reactions
      Last Post SEQadmin2  
      Started by SEQadmin2, 06-26-2026, 11:10 AM
      0 responses
      19 views
      0 reactions
      Last Post SEQadmin2  
      Started by SEQadmin2, 06-17-2026, 06:09 AM
      0 responses
      53 views
      0 reactions
      Last Post SEQadmin2  
      Working...