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  • Sophie GAIANI
    Junior Member
    • Dec 2011
    • 1

    Singleton quantification in pair-end experiment (RNA-seq)?

    Hi,
    I want to quantify RNA expression in 10 samples.
    So I performed a RNA-seq experiment on Illumina HiSeq 2000 platform (2 x 90 nt).

    I used Cole Trapnell method in order to analyse my reads (Differential gene and transcript expression analysis of RNA-seq experiments with TopHat and Cufflinks; Nature Protocols Volume: 7, Pages: 562–578 Year published: (2012) DOI: doi:10.1038/nprot.2012.016 ). The aim of my analysis is to perform a differential analysis focused on well known human transcriptome.
    So Cole Trapnell suggest to perform a Tophat alignement followed by a cuffdiff.

    I needed to explore each step of this protocol.
    Tophat output (accepted_hits.bam) is composed of ~3% of reads mapped at several loci, 85% reads called "properly paired" according to tophat parameters, 2% reads called "not properly paired" with a big insert between both reads and 10% of singletons (reads which lost their mate-pair).

    My question is: does cuffdiff include singletons in FPKM calculation?

    Thanks by advance,
    best
    Sophie
    Sophie
  • win804
    Member
    • Apr 2010
    • 18

    #2
    Hi,
    I have the same question here.
    Also, what happens to singletons?

    Any input is much appreciated.
    Thanks a lot.

    Comment

    • paulorapazote
      Member
      • May 2012
      • 19

      #3
      Singletons

      Hi

      I have the same question. Apparently no, singletons are not used in the FPKM calculations. I found that in this link:


      Comment

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