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  • Rachelly
    Member
    • Oct 2010
    • 37

    Cufflinks differential expression problem

    Hi all,

    When running CuffDiff I got the following results for 3 samples:
    Sample 1 FPKM - 47.01
    Sample 2 FPKM - 0
    Sample 3 FPKM - 0

    And for the differential test:
    ln(FC) test p-value significance
    Sample1 vs. Sample 2 -1.79769e+308 NOTEST 0 no
    Sample1 vs. Sample 3 -1.79769e+308 OK 0 yes

    If both Sample2 and Sample 3 have an FPKM value of 0 why is there a difference in the differential expression?
    Why wasn't a test conducted for the first pair? If there were enough fragments to conduct the test for the second pair, there should be enough for the first...

    Thanks,
    Rachelly.
  • Cole Trapnell
    Senior Member
    • Nov 2008
    • 213

    #2
    Can you send the mapped reads for this locus in each sample as a test example to our support mailing address? It's hard to say what's going on here just from these results.

    Comment

    • Rachelly
      Member
      • Oct 2010
      • 37

      #3
      Thanks for your reply Cole!
      I sent you the reads to the help address just now.

      Rachelly.

      Comment

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