Seqanswers Leaderboard Ad

Collapse

Announcement

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

  • Low Quality Reverse read Miseq

    Hello every one

    i work with Miseq illumina using V2 chemistry (500 cycles) and in the last runs i´ve had a problem with the quality of the reverse read; the forward read has a Q30 <90%, but the reverse decrease at point of 12% on mi last run. Has anyone idea of the possible reason?

    This was mi last run, the cartridge is for 500 cycles but only i used 181 and 181
    Click image for larger version

Name:	image.png
Views:	258
Size:	247.8 KB
ID:	324506

  • #2
    valeriagomez99 has this happened more than once? I can't understand why the quality would drop so low. Also, what kind of samples were you running?

    Comment


    • #3
      This have happened several times. The samples for this run were microsatellites, but 16s and ITS amplicons have had the same problem. i used expired cartridge, but if this were the problem i think that forward read quality also would be affected

      Comment


      • #4
        valeriagomez99 yeah that doesn't sound good. Have you spoken to Illumina about this? I'm going to assume it's something wrong with the MiSeq because clearly, something is going wrong right before or during read 2. And I've used tons of expired cartridges and had no issues, unless they were accidentally thawed and refrozen.

        Comment


        • #5
          Ben3, yes the illumina personal checked the Miseq and all is well, and between the failed runs we have used new cartridges and the sequencing finished fine with a good reverse, this only happens with expired cartridges which makes us think it may be the cause, the cartridge always remains frozen in any case.

          Comment

          Latest Articles

          Collapse

          • seqadmin
            Exploring the Dynamics of the Tumor Microenvironment
            by seqadmin




            The complexity of cancer is clearly demonstrated in the diverse ecosystem of the tumor microenvironment (TME). The TME is made up of numerous cell types and its development begins with the changes that happen during oncogenesis. “Genomic mutations, copy number changes, epigenetic alterations, and alternative gene expression occur to varying degrees within the affected tumor cells,” explained Andrea O’Hara, Ph.D., Strategic Technical Specialist at Azenta. “As...
            07-08-2024, 03:19 PM
          • seqadmin
            Exploring Human Diversity Through Large-Scale Omics
            by seqadmin


            In 2003, researchers from the Human Genome Project (HGP) announced the most comprehensive genome to date1. Although the genome wasn’t fully completed until nearly 20 years later2, numerous large-scale projects, such as the International HapMap Project and 1000 Genomes Project, continued the HGP's work, capturing extensive variation and genomic diversity within humans. Recently, newer initiatives have significantly increased in scale and expanded beyond genomics, offering a more detailed...
            06-25-2024, 06:43 AM

          ad_right_rmr

          Collapse

          News

          Collapse

          Topics Statistics Last Post
          Started by seqadmin, 07-16-2024, 05:49 AM
          0 responses
          28 views
          0 likes
          Last Post seqadmin  
          Started by seqadmin, 07-15-2024, 06:53 AM
          0 responses
          34 views
          0 likes
          Last Post seqadmin  
          Started by seqadmin, 07-10-2024, 07:30 AM
          0 responses
          40 views
          0 likes
          Last Post seqadmin  
          Started by seqadmin, 07-03-2024, 09:45 AM
          0 responses
          205 views
          0 likes
          Last Post seqadmin  
          Working...
          X