crc-rna-seq-salmon

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        MultiQC: Summarize analysis results for multiple tools and samples in a single report
        Philip Ewels, Måns Magnusson, Sverker Lundin and Max Käller
        Bioinformatics (2016)
        doi: 10.1093/bioinformatics/btw354
        PMID: 27312411
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        This report was generated using MultiQC, version 1.31

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        MultiQC is published in Bioinformatics:

        MultiQC: Summarize analysis results for multiple tools and samples in a single report
        Philip Ewels, Måns Magnusson, Sverker Lundin and Max Käller
        Bioinformatics (2016)
        doi: 10.1093/bioinformatics/btw354
        PMID: 27312411

        crc-rna-seq-salmon

        A modular tool to aggregate results from bioinformatics analyses across many samples into a single report.

        This report has been generated by the nf-core/rnaseq analysis pipeline. For information about how to interpret these results, please see the documentation.
        Report generated on 2025-11-29, 18:47 CET based on data in: /tmp/nxf.zWS11fd0qN

        General Statistics

        Showing 126/126 rows and 11/18 columns.
        Sample Name% AlignedM AlignedLibrary typesCFRM BiasDupsGCAvg lenMedian lenFailedSeqsTrimmed basesDupsGCAvg lenMedian lenFailedSeqs
        SRR17866817
        92.2%
        25.7M
        ISR
        100.0%
        0.0
        SRR17866817_1
        65.3%
        48.0%
        57bp
        57bp
        18%
        27.9M
        1.2%
        65.3%
        48.0%
        56bp
        56bp
        18%
        27.9M
        SRR17866817_2
        60.8%
        49.0%
        57bp
        57bp
        18%
        27.9M
        1.4%
        60.8%
        49.0%
        56bp
        56bp
        18%
        27.9M
        SRR17866818
        93.5%
        19.6M
        ISR
        100.0%
        0.0
        SRR17866818_1
        67.4%
        48.0%
        57bp
        57bp
        18%
        21.0M
        1.2%
        67.4%
        48.0%
        56bp
        56bp
        18%
        21.0M
        SRR17866818_2
        63.3%
        49.0%
        57bp
        57bp
        18%
        21.0M
        1.5%
        63.3%
        49.0%
        56bp
        56bp
        18%
        21.0M
        SRR17866819
        91.5%
        24.5M
        ISR
        100.0%
        0.0
        SRR17866819_1
        65.3%
        49.0%
        57bp
        57bp
        18%
        26.9M
        1.2%
        65.3%
        49.0%
        56bp
        56bp
        18%
        26.8M
        SRR17866819_2
        62.8%
        50.0%
        57bp
        57bp
        18%
        26.9M
        1.4%
        62.8%
        50.0%
        56bp
        56bp
        18%
        26.8M
        SRR17866820
        90.5%
        26.4M
        ISR
        100.0%
        0.0
        SRR17866820_1
        69.4%
        49.0%
        57bp
        57bp
        18%
        29.2M
        1.2%
        69.4%
        49.0%
        56bp
        56bp
        18%
        29.2M
        SRR17866820_2
        66.6%
        50.0%
        57bp
        57bp
        18%
        29.2M
        1.5%
        66.6%
        49.0%
        56bp
        56bp
        18%
        29.2M
        SRR17866821
        94.5%
        24.9M
        ISR
        100.0%
        0.0
        SRR17866821_1
        68.9%
        48.0%
        57bp
        57bp
        18%
        26.4M
        1.2%
        68.9%
        48.0%
        56bp
        56bp
        18%
        26.3M
        SRR17866821_2
        70.5%
        50.0%
        57bp
        57bp
        27%
        26.4M
        1.4%
        70.5%
        49.0%
        56bp
        56bp
        27%
        26.3M
        SRR17866822
        93.6%
        21.8M
        ISR
        100.0%
        0.0
        SRR17866822_1
        67.9%
        48.0%
        57bp
        57bp
        18%
        23.3M
        1.2%
        67.9%
        48.0%
        56bp
        56bp
        18%
        23.3M
        SRR17866822_2
        68.1%
        49.0%
        57bp
        57bp
        27%
        23.3M
        1.4%
        68.1%
        49.0%
        56bp
        56bp
        27%
        23.3M
        SRR17866823
        94.9%
        31.2M
        ISR
        100.0%
        0.0
        SRR17866823_1
        71.0%
        48.0%
        57bp
        57bp
        18%
        32.9M
        1.4%
        70.9%
        48.0%
        56bp
        56bp
        18%
        32.8M
        SRR17866823_2
        68.7%
        50.0%
        57bp
        57bp
        27%
        32.9M
        1.5%
        68.7%
        49.0%
        56bp
        56bp
        27%
        32.8M
        SRR17866824
        92.3%
        29.9M
        ISR
        100.0%
        0.0
        SRR17866824_1
        70.3%
        49.0%
        57bp
        57bp
        18%
        32.4M
        1.2%
        70.2%
        49.0%
        56bp
        56bp
        18%
        32.4M
        SRR17866824_2
        67.7%
        50.0%
        57bp
        57bp
        27%
        32.4M
        1.6%
        67.7%
        50.0%
        56bp
        56bp
        27%
        32.4M
        SRR17866825
        92.7%
        24.7M
        ISR
        100.0%
        0.0
        SRR17866825_1
        64.2%
        48.0%
        57bp
        57bp
        18%
        26.7M
        1.2%
        64.2%
        48.0%
        56bp
        56bp
        18%
        26.7M
        SRR17866825_2
        63.7%
        49.0%
        57bp
        57bp
        18%
        26.7M
        1.4%
        63.7%
        49.0%
        56bp
        56bp
        27%
        26.7M
        SRR17866826
        93.4%
        28.0M
        ISR
        100.0%
        0.0
        SRR17866826_1
        72.0%
        48.0%
        57bp
        57bp
        18%
        30.0M
        1.1%
        71.9%
        48.0%
        56bp
        56bp
        18%
        30.0M
        SRR17866826_2
        69.2%
        49.0%
        57bp
        57bp
        18%
        30.0M
        1.5%
        69.2%
        48.0%
        56bp
        56bp
        18%
        30.0M
        SRR17866827
        89.3%
        24.8M
        ISR
        100.0%
        0.0
        SRR17866827_1
        61.8%
        49.0%
        57bp
        57bp
        18%
        27.8M
        1.2%
        61.7%
        49.0%
        56bp
        56bp
        18%
        27.8M
        SRR17866827_2
        58.8%
        50.0%
        57bp
        57bp
        18%
        27.8M
        1.5%
        58.8%
        50.0%
        56bp
        56bp
        18%
        27.8M
        SRR17866828
        94.1%
        33.9M
        ISR
        100.0%
        0.0
        SRR17866828_1
        71.9%
        49.0%
        57bp
        57bp
        18%
        36.1M
        1.2%
        71.9%
        49.0%
        56bp
        56bp
        18%
        36.0M
        SRR17866828_2
        71.7%
        50.0%
        57bp
        57bp
        27%
        36.1M
        1.5%
        71.7%
        50.0%
        56bp
        56bp
        27%
        36.0M
        SRR17866829
        92.1%
        28.6M
        ISR
        100.0%
        0.0
        SRR17866829_1
        67.9%
        49.0%
        57bp
        57bp
        18%
        31.1M
        1.2%
        67.9%
        49.0%
        56bp
        56bp
        18%
        31.0M
        SRR17866829_2
        64.9%
        50.0%
        57bp
        57bp
        18%
        31.1M
        1.5%
        64.9%
        49.0%
        56bp
        56bp
        18%
        31.0M
        SRR17866830
        93.9%
        33.5M
        ISR
        100.0%
        0.0
        SRR17866830_1
        76.2%
        48.0%
        57bp
        57bp
        18%
        35.8M
        1.1%
        76.2%
        47.0%
        56bp
        56bp
        18%
        35.7M
        SRR17866830_2
        73.6%
        49.0%
        57bp
        57bp
        18%
        35.8M
        1.5%
        73.6%
        48.0%
        56bp
        56bp
        18%
        35.7M
        SRR17866831
        93.1%
        31.7M
        ISR
        100.0%
        0.0
        SRR17866831_1
        75.1%
        48.0%
        57bp
        57bp
        18%
        34.0M
        1.1%
        75.1%
        47.0%
        56bp
        56bp
        18%
        34.0M
        SRR17866831_2
        73.4%
        49.0%
        57bp
        57bp
        27%
        34.0M
        1.5%
        73.4%
        48.0%
        56bp
        56bp
        27%
        34.0M
        SRR17866832
        88.7%
        27.5M
        ISR
        100.0%
        0.0
        SRR17866832_1
        70.1%
        49.0%
        57bp
        57bp
        18%
        31.0M
        1.1%
        70.1%
        48.0%
        56bp
        56bp
        18%
        31.0M
        SRR17866832_2
        67.1%
        49.0%
        57bp
        57bp
        18%
        31.0M
        1.4%
        67.2%
        49.0%
        56bp
        56bp
        18%
        31.0M
        SRR17866833
        93.7%
        32.6M
        ISR
        100.0%
        0.0
        SRR17866833_1
        63.5%
        49.0%
        57bp
        57bp
        18%
        34.8M
        1.3%
        63.5%
        49.0%
        56bp
        56bp
        18%
        34.8M
        SRR17866833_2
        63.8%
        51.0%
        57bp
        57bp
        18%
        34.8M
        1.4%
        63.9%
        50.0%
        56bp
        56bp
        18%
        34.8M
        SRR17866834
        94.2%
        33.1M
        ISR
        100.0%
        0.0
        SRR17866834_1
        71.2%
        49.0%
        57bp
        57bp
        18%
        35.2M
        1.2%
        71.1%
        49.0%
        56bp
        56bp
        18%
        35.1M
        SRR17866834_2
        67.9%
        50.0%
        57bp
        57bp
        18%
        35.2M
        1.6%
        67.9%
        49.0%
        56bp
        56bp
        18%
        35.1M
        SRR17866835
        93.6%
        78.9M
        ISR
        100.0%
        0.0
        SRR17866835_1
        77.8%
        48.0%
        57bp
        57bp
        18%
        84.5M
        1.1%
        77.8%
        47.0%
        56bp
        56bp
        18%
        84.3M
        SRR17866835_2
        77.4%
        48.0%
        57bp
        57bp
        27%
        84.5M
        1.5%
        77.4%
        48.0%
        56bp
        56bp
        27%
        84.3M
        SRR17866836
        93.6%
        24.8M
        ISR
        100.0%
        0.0
        SRR17866836_1
        68.8%
        48.0%
        57bp
        57bp
        18%
        26.5M
        1.2%
        68.8%
        48.0%
        56bp
        56bp
        18%
        26.4M
        SRR17866836_2
        66.1%
        49.0%
        57bp
        57bp
        27%
        26.5M
        1.4%
        66.1%
        49.0%
        56bp
        56bp
        27%
        26.4M
        SRR17866837
        95.2%
        27.4M
        ISR
        100.0%
        0.0
        SRR17866837_1
        69.0%
        48.0%
        57bp
        57bp
        18%
        28.8M
        1.2%
        69.0%
        47.0%
        56bp
        56bp
        18%
        28.8M
        SRR17866837_2
        66.4%
        49.0%
        57bp
        57bp
        27%
        28.8M
        1.4%
        66.4%
        48.0%
        56bp
        56bp
        27%
        28.8M
        SRR17866838
        93.9%
        36.9M
        ISR
        100.0%
        0.0
        SRR17866838_1
        72.1%
        50.0%
        57bp
        57bp
        18%
        39.3M
        1.2%
        72.1%
        49.0%
        56bp
        56bp
        18%
        39.3M
        SRR17866838_2
        70.9%
        51.0%
        57bp
        57bp
        18%
        39.3M
        1.5%
        70.9%
        50.0%
        56bp
        56bp
        18%
        39.3M
        SRR17866839
        94.0%
        26.5M
        ISR
        100.0%
        0.0
        SRR17866839_1
        70.7%
        49.0%
        57bp
        57bp
        18%
        28.2M
        1.2%
        70.7%
        49.0%
        56bp
        56bp
        18%
        28.1M
        SRR17866839_2
        67.1%
        50.0%
        57bp
        57bp
        18%
        28.2M
        1.4%
        67.1%
        50.0%
        56bp
        56bp
        18%
        28.1M
        SRR17866840
        93.4%
        29.5M
        ISR
        100.0%
        0.0
        SRR17866840_1
        70.8%
        48.0%
        57bp
        57bp
        18%
        31.6M
        1.2%
        70.8%
        48.0%
        56bp
        56bp
        18%
        31.6M
        SRR17866840_2
        67.4%
        49.0%
        57bp
        57bp
        18%
        31.6M
        1.5%
        67.4%
        49.0%
        56bp
        56bp
        18%
        31.6M
        SRR17866841
        90.2%
        27.3M
        ISR
        100.0%
        0.0
        SRR17866841_1
        65.1%
        48.0%
        57bp
        57bp
        18%
        30.3M
        1.2%
        65.0%
        48.0%
        56bp
        56bp
        18%
        30.3M
        SRR17866841_2
        62.1%
        49.0%
        57bp
        57bp
        18%
        30.3M
        1.4%
        62.1%
        49.0%
        56bp
        56bp
        18%
        30.3M
        SRR17866842
        90.2%
        22.2M
        ISR
        100.0%
        0.0
        SRR17866842_1
        68.1%
        48.0%
        57bp
        57bp
        18%
        24.6M
        1.2%
        68.1%
        48.0%
        56bp
        56bp
        18%
        24.6M
        SRR17866842_2
        69.3%
        49.0%
        57bp
        57bp
        27%
        24.6M
        1.4%
        69.3%
        49.0%
        56bp
        56bp
        27%
        24.6M
        SRR17866843
        93.9%
        37.4M
        ISR
        100.0%
        0.0
        SRR17866843_1
        74.3%
        51.0%
        57bp
        57bp
        18%
        39.9M
        1.3%
        74.2%
        51.0%
        56bp
        56bp
        18%
        39.8M
        SRR17866843_2
        72.1%
        52.0%
        57bp
        57bp
        27%
        39.9M
        1.5%
        72.1%
        52.0%
        56bp
        56bp
        27%
        39.8M
        SRR17866844
        91.4%
        29.7M
        ISR
        100.0%
        0.0
        SRR17866844_1
        72.8%
        51.0%
        57bp
        57bp
        18%
        32.8M
        1.8%
        72.6%
        50.0%
        56bp
        56bp
        18%
        32.5M
        SRR17866844_2
        70.7%
        52.0%
        57bp
        57bp
        27%
        32.8M
        2.1%
        70.5%
        51.0%
        56bp
        56bp
        27%
        32.5M
        SRR17866845
        93.3%
        24.4M
        ISR
        100.0%
        0.0
        SRR17866845_1
        69.0%
        49.0%
        57bp
        57bp
        18%
        26.2M
        1.3%
        68.9%
        49.0%
        56bp
        56bp
        18%
        26.1M
        SRR17866845_2
        67.3%
        50.0%
        57bp
        57bp
        18%
        26.2M
        1.6%
        67.3%
        50.0%
        56bp
        56bp
        18%
        26.1M
        SRR17866846
        93.4%
        31.2M
        ISR
        100.0%
        0.0
        SRR17866846_1
        70.8%
        50.0%
        57bp
        57bp
        18%
        33.5M
        1.3%
        70.7%
        49.0%
        56bp
        56bp
        18%
        33.4M
        SRR17866846_2
        68.8%
        51.0%
        57bp
        57bp
        18%
        33.5M
        1.6%
        68.8%
        50.0%
        56bp
        56bp
        18%
        33.4M
        SRR17866847
        89.3%
        25.6M
        ISR
        100.0%
        0.0
        SRR17866847_1
        66.4%
        50.0%
        57bp
        57bp
        18%
        28.8M
        1.3%
        66.4%
        50.0%
        56bp
        56bp
        18%
        28.7M
        SRR17866847_2
        64.5%
        51.0%
        57bp
        57bp
        18%
        28.8M
        1.6%
        64.5%
        50.0%
        56bp
        56bp
        18%
        28.7M
        SRR17866848
        93.7%
        32.1M
        ISR
        100.0%
        0.0
        SRR17866848_1
        69.5%
        50.0%
        57bp
        57bp
        18%
        34.3M
        1.3%
        69.5%
        49.0%
        56bp
        56bp
        18%
        34.2M
        SRR17866848_2
        66.5%
        51.0%
        57bp
        57bp
        18%
        34.3M
        1.5%
        66.5%
        50.0%
        56bp
        56bp
        18%
        34.2M
        SRR17866849
        92.8%
        34.0M
        ISR
        100.0%
        0.0
        SRR17866849_1
        65.4%
        49.0%
        57bp
        57bp
        18%
        36.7M
        1.3%
        65.4%
        49.0%
        56bp
        56bp
        18%
        36.7M
        SRR17866849_2
        61.9%
        50.0%
        57bp
        57bp
        18%
        36.7M
        1.5%
        61.9%
        50.0%
        56bp
        56bp
        18%
        36.7M
        SRR17866850
        93.1%
        25.0M
        ISR
        100.0%
        0.0
        SRR17866850_1
        74.5%
        51.0%
        57bp
        57bp
        18%
        27.0M
        1.7%
        74.4%
        50.0%
        56bp
        56bp
        18%
        26.8M
        SRR17866850_2
        72.4%
        51.0%
        57bp
        57bp
        18%
        27.0M
        2.0%
        72.3%
        51.0%
        56bp
        56bp
        18%
        26.8M
        SRR17866851
        83.7%
        29.1M
        ISR
        100.0%
        0.0
        SRR17866851_1
        70.2%
        50.0%
        57bp
        57bp
        18%
        34.7M
        1.2%
        70.2%
        50.0%
        56bp
        56bp
        18%
        34.7M
        SRR17866851_2
        66.3%
        51.0%
        57bp
        57bp
        18%
        34.7M
        1.4%
        66.3%
        51.0%
        56bp
        56bp
        18%
        34.7M
        SRR17866852
        86.2%
        24.3M
        ISR
        100.0%
        0.0
        SRR17866852_1
        65.0%
        51.0%
        57bp
        57bp
        27%
        28.2M
        1.3%
        65.0%
        50.0%
        56bp
        56bp
        27%
        28.2M
        SRR17866852_2
        62.7%
        52.0%
        57bp
        57bp
        36%
        28.2M
        1.4%
        62.7%
        51.0%
        56bp
        56bp
        36%
        28.2M
        SRR17866853
        94.3%
        28.6M
        ISR
        100.0%
        0.0
        SRR17866853_1
        80.9%
        47.0%
        57bp
        57bp
        18%
        30.4M
        1.1%
        80.9%
        47.0%
        56bp
        56bp
        18%
        30.3M
        SRR17866853_2
        78.1%
        48.0%
        57bp
        57bp
        18%
        30.4M
        1.5%
        78.1%
        48.0%
        56bp
        56bp
        18%
        30.3M
        SRR17866854
        86.6%
        29.9M
        ISR
        100.0%
        0.0
        SRR17866854_1
        71.5%
        49.0%
        151bp
        151bp
        27%
        34.6M
        12.0%
        71.4%
        49.0%
        133bp
        142bp
        18%
        34.5M
        SRR17866854_2
        71.0%
        49.0%
        151bp
        151bp
        27%
        34.6M
        12.2%
        70.9%
        49.0%
        133bp
        142bp
        18%
        34.5M
        SRR17866855
        78.8%
        25.5M
        ISR
        100.0%
        0.0
        SRR17866855_1
        85.0%
        50.0%
        57bp
        57bp
        18%
        32.5M
        1.4%
        84.9%
        50.0%
        56bp
        56bp
        18%
        32.4M
        SRR17866855_2
        82.8%
        52.0%
        57bp
        57bp
        18%
        32.5M
        1.6%
        82.8%
        51.0%
        56bp
        56bp
        18%
        32.4M
        SRR17866856
        94.4%
        25.0M
        ISR
        100.0%
        0.0
        SRR17866856_1
        70.4%
        49.0%
        57bp
        57bp
        18%
        26.6M
        1.2%
        70.4%
        48.0%
        56bp
        56bp
        18%
        26.5M
        SRR17866856_2
        68.6%
        50.0%
        57bp
        57bp
        18%
        26.6M
        1.5%
        68.6%
        49.0%
        56bp
        56bp
        18%
        26.5M
        SRR17866857
        95.1%
        29.7M
        ISR
        100.0%
        0.0
        SRR17866857_1
        73.5%
        49.0%
        57bp
        57bp
        18%
        31.3M
        1.4%
        73.4%
        48.0%
        56bp
        56bp
        18%
        31.2M
        SRR17866857_2
        69.3%
        50.0%
        57bp
        57bp
        18%
        31.3M
        1.6%
        69.3%
        50.0%
        56bp
        56bp
        18%
        31.2M
        SRR17866858
        94.5%
        29.6M
        ISR
        100.0%
        0.0
        SRR17866858_1
        71.6%
        50.0%
        57bp
        57bp
        18%
        31.3M
        1.3%
        71.6%
        49.0%
        56bp
        56bp
        18%
        31.3M
        SRR17866858_2
        68.6%
        51.0%
        57bp
        57bp
        27%
        31.3M
        1.6%
        68.6%
        50.0%
        56bp
        56bp
        27%
        31.3M

        FastQC (raw)

        This section of the report shows FastQC results before adapter trimming.URL: http://www.bioinformatics.babraham.ac.uk/projects/fastqc

        Sequence Counts

        Sequence counts for each sample. Duplicate read counts are an estimate only.

        This plot show the total number of reads, broken down into unique and duplicate if possible (only more recent versions of FastQC give duplicate info).

        You can read more about duplicate calculation in the FastQC documentation. A small part has been copied here for convenience:

        Only sequences which first appear in the first 100,000 sequences in each file are analysed. This should be enough to get a good impression for the duplication levels in the whole file. Each sequence is tracked to the end of the file to give a representative count of the overall duplication level.

        The duplication detection requires an exact sequence match over the whole length of the sequence. Any reads over 75bp in length are truncated to 50bp for this analysis.

        Created with MultiQC

        Sequence Quality Histograms

        The mean quality value across each base position in the read.

        To enable multiple samples to be plotted on the same graph, only the mean quality scores are plotted (unlike the box plots seen in FastQC reports).

        Taken from the FastQC help:

        The y-axis on the graph shows the quality scores. The higher the score, the better the base call. The background of the graph divides the y axis into very good quality calls (green), calls of reasonable quality (orange), and calls of poor quality (red). The quality of calls on most platforms will degrade as the run progresses, so it is common to see base calls falling into the orange area towards the end of a read.

        Created with MultiQC

        Per Sequence Quality Scores

        The number of reads with average quality scores. Shows if a subset of reads has poor quality.

        From the FastQC help:

        The per sequence quality score report allows you to see if a subset of your sequences have universally low quality values. It is often the case that a subset of sequences will have universally poor quality, however these should represent only a small percentage of the total sequences.

        Created with MultiQC

        Per Base Sequence Content

        The proportion of each base position for which each of the four normal DNA bases has been called.

        To enable multiple samples to be shown in a single plot, the base composition data is shown as a heatmap. The colours represent the balance between the four bases: an even distribution should give an even muddy brown colour. Hover over the plot to see the percentage of the four bases under the cursor.

        To see the data as a line plot, as in the original FastQC graph, click on a sample track.

        From the FastQC help:

        Per Base Sequence Content plots out the proportion of each base position in a file for which each of the four normal DNA bases has been called.

        In a random library you would expect that there would be little to no difference between the different bases of a sequence run, so the lines in this plot should run parallel with each other. The relative amount of each base should reflect the overall amount of these bases in your genome, but in any case they should not be hugely imbalanced from each other.

        It's worth noting that some types of library will always produce biased sequence composition, normally at the start of the read. Libraries produced by priming using random hexamers (including nearly all RNA-Seq libraries) and those which were fragmented using transposases inherit an intrinsic bias in the positions at which reads start. This bias does not concern an absolute sequence, but instead provides enrichement of a number of different K-mers at the 5' end of the reads. Whilst this is a true technical bias, it isn't something which can be corrected by trimming and in most cases doesn't seem to adversely affect the downstream analysis.

        Click a sample row to see a line plot for that dataset.
        Rollover for sample name
        Position: -
        %T: -
        %C: -
        %A: -
        %G: -

        Per Sequence GC Content

        The average GC content of reads. Normal random library typically have a roughly normal distribution of GC content.

        From the FastQC help:

        This module measures the GC content across the whole length of each sequence in a file and compares it to a modelled normal distribution of GC content.

        In a normal random library you would expect to see a roughly normal distribution of GC content where the central peak corresponds to the overall GC content of the underlying genome. Since we don't know the GC content of the genome the modal GC content is calculated from the observed data and used to build a reference distribution.

        An unusually shaped distribution could indicate a contaminated library or some other kinds of biased subset. A normal distribution which is shifted indicates some systematic bias which is independent of base position. If there is a systematic bias which creates a shifted normal distribution then this won't be flagged as an error by the module since it doesn't know what your genome's GC content should be.

        Created with MultiQC

        Per Base N Content

        The percentage of base calls at each position for which an N was called.

        From the FastQC help:

        If a sequencer is unable to make a base call with sufficient confidence then it will normally substitute an N rather than a conventional base call. This graph shows the percentage of base calls at each position for which an N was called.

        It's not unusual to see a very low proportion of Ns appearing in a sequence, especially nearer the end of a sequence. However, if this proportion rises above a few percent it suggests that the analysis pipeline was unable to interpret the data well enough to make valid base calls.

        Created with MultiQC

        Sequence Length Distribution

        The distribution of fragment sizes (read lengths) found. See the FastQC help

        Created with MultiQC

        Sequence Duplication Levels

        The relative level of duplication found for every sequence.

        From the FastQC Help:

        In a diverse library most sequences will occur only once in the final set. A low level of duplication may indicate a very high level of coverage of the target sequence, but a high level of duplication is more likely to indicate some kind of enrichment bias (e.g. PCR over amplification). This graph shows the degree of duplication for every sequence in a library: the relative number of sequences with different degrees of duplication.

        Only sequences which first appear in the first 100,000 sequences in each file are analysed. This should be enough to get a good impression for the duplication levels in the whole file. Each sequence is tracked to the end of the file to give a representative count of the overall duplication level.

        The duplication detection requires an exact sequence match over the whole length of the sequence. Any reads over 75bp in length are truncated to 50bp for this analysis.

        In a properly diverse library most sequences should fall into the far left of the plot in both the red and blue lines. A general level of enrichment, indicating broad oversequencing in the library will tend to flatten the lines, lowering the low end and generally raising other categories. More specific enrichments of subsets, or the presence of low complexity contaminants will tend to produce spikes towards the right of the plot.

        Created with MultiQC

        Overrepresented sequences by sample

        The total amount of overrepresented sequences found in each library.

        FastQC calculates and lists overrepresented sequences in FastQ files. It would not be possible to show this for all samples in a MultiQC report, so instead this plot shows the number of sequences categorized as overrepresented.

        Sometimes, a single sequence may account for a large number of reads in a dataset. To show this, the bars are split into two: the first shows the overrepresented reads that come from the single most common sequence. The second shows the total count from all remaining overrepresented sequences.

        From the FastQC Help:

        A normal high-throughput library will contain a diverse set of sequences, with no individual sequence making up a tiny fraction of the whole. Finding that a single sequence is very overrepresented in the set either means that it is highly biologically significant, or indicates that the library is contaminated, or not as diverse as you expected.

        FastQC lists all the sequences which make up more than 0.1% of the total. To conserve memory only sequences which appear in the first 100,000 sequences are tracked to the end of the file. It is therefore possible that a sequence which is overrepresented but doesn't appear at the start of the file for some reason could be missed by this module.

        84 samples had less than 1% of reads made up of overrepresented sequences

        Top overrepresented sequences

        Top overrepresented sequences across all samples. The table shows 20 most overrepresented sequences across all samples, ranked by the number of samples they occur in.

        Showing 20/20 rows and 3/3 columns.
        Overrepresented sequenceReportsOccurrences% of all reads
        TCCCGTATCGAAGGCCTTTTTGGACAGGTGGTGTGTGGTGGCCTTGGTAT
        17
        688207
        0.0256%
        TCACATGCCTATCATATAGTAAAACCCAGCCCATGACCCCTAACAGGGGC
        10
        407889
        0.0152%
        ACTGTCTCTTATACACATCTGACGCTGCCGACGAACGTTCCTTAGTGTAG
        1
        172094
        0.0064%
        TCCTCACCCGGCCCGGACACGGACAGGATTGACAGATTGATAGCTCTTTC
        2
        137731
        0.0051%
        TCTGTCTCTTATACACATCTCCGAGCCCACGAGACACGCCTTGTTATCTC
        1
        125482
        0.0047%
        ACTGTCTCTTATACACATCTGACGCTGCCGACGATGGTAGAGATGTGTAG
        1
        123555
        0.0046%
        TCTGTCTCTTATACACATCTCCGAGCCCACGAGACAGATCCATTAATCTC
        1
        95043
        0.0035%
        TCCTGCCAGTAGCATATGCTTGTCTCAAAGATTAAGCCATGCATGTCTAA
        1
        64728
        0.0024%
        CTGTCTCTTATACACATCTGACGCTGCCGACGACCTTCTAACAGTGTAGA
        1
        53743
        0.0020%
        TCTGTCTCTTATACACATCTCCGAGCCCACGAGACACGCCTTGTTATCGC
        1
        46672
        0.0017%
        TGTGAAAGATGAGCTGGAGGACCGCAATAGGGGTAGGTCCCCTGTGGAAA
        1
        45884
        0.0017%
        TCTGTCTCTTATACACATCTCCGAGCCCACGAGACTATTGCGCTCATCTC
        1
        44268
        0.0016%
        ACTGTCTCTTATACACATCTGACGCTGCCGACGAAATATTGCCAGTGTAG
        1
        39868
        0.0015%
        ACTGTCTCTTATACACATCTGACGCTGCCGACGATTCAGTTGTCGTGTAG
        1
        39793
        0.0015%
        CTGTCTCTTATACACATCTCCGAGCCCACGAGACTTCATAAGGTATCTCG
        1
        35901
        0.0013%
        TGTCGGCATGTATTAGCTCTAGAATTACCACAGTTATCCAAGTAGGAGAG
        1
        34165
        0.0013%
        TGGCAGACGTTCGAATGGGTCGTCGCCGCCACGGGGGGCGTGCGATCGGC
        1
        33916
        0.0013%
        TGGGGGCTTCAATCGGGAGTACTACTCGATTGTCAACGTCAAGGAGTCGC
        1
        30514
        0.0011%
        TCTGTCTCTTATACACATCTCCGAGCCCACGAGACAGATCCATTAATCGC
        1
        30275
        0.0011%
        ACTGTCTCTTATACACATCTGACGCTGCCGACGACGCGGTGATCGTGTAG
        1
        28987
        0.0011%

        Adapter Content

        The cumulative percentage count of the proportion of your library which has seen each of the adapter sequences at each position.

        Note that only samples with ≥ 0.1% adapter contamination are shown.

        There may be several lines per sample, as one is shown for each adapter detected in the file.

        From the FastQC Help:

        The plot shows a cumulative percentage count of the proportion of your library which has seen each of the adapter sequences at each position. Once a sequence has been seen in a read it is counted as being present right through to the end of the read so the percentages you see will only increase as the read length goes on.

        Created with MultiQC

        Status Checks

        Status for each FastQC section showing whether results seem entirely normal (green), slightly abnormal (orange) or very unusual (red).

        FastQC assigns a status for each section of the report. These give a quick evaluation of whether the results of the analysis seem entirely normal (green), slightly abnormal (orange) or very unusual (red).

        It is important to stress that although the analysis results appear to give a pass/fail result, these evaluations must be taken in the context of what you expect from your library. A 'normal' sample as far as FastQC is concerned is random and diverse. Some experiments may be expected to produce libraries which are biased in particular ways. You should treat the summary evaluations therefore as pointers to where you should concentrate your attention and understand why your library may not look random and diverse.

        Specific guidance on how to interpret the output of each module can be found in the relevant report section, or in the FastQC help.

        In this heatmap, we summarise all of these into a single heatmap for a quick overview. Note that not all FastQC sections have plots in MultiQC reports, but all status checks are shown in this heatmap.

        Created with MultiQC

        Cutadapt

        Finds and removes adapter sequences, primers, poly-A tails, and other types of unwanted sequences.URL: https://cutadapt.readthedocs.ioDOI: 10.14806/ej.17.1.200

        Filtered Reads

        This plot shows the number of reads (SE) / pairs (PE) removed by Cutadapt.

        Created with MultiQC

        Trimmed Sequence Lengths (3')

        This plot shows the number of reads with certain lengths of adapter trimmed for the 3' end.

        Obs/Exp shows the raw counts divided by the number expected due to sequencing errors. A defined peak may be related to adapter length.

        See the cutadapt documentation for more information on how these numbers are generated.

        Created with MultiQC

        FastQC (trimmed)

        This section of the report shows FastQC results after adapter trimming.URL: http://www.bioinformatics.babraham.ac.uk/projects/fastqc

        Sequence Counts

        Sequence counts for each sample. Duplicate read counts are an estimate only.

        This plot show the total number of reads, broken down into unique and duplicate if possible (only more recent versions of FastQC give duplicate info).

        You can read more about duplicate calculation in the FastQC documentation. A small part has been copied here for convenience:

        Only sequences which first appear in the first 100,000 sequences in each file are analysed. This should be enough to get a good impression for the duplication levels in the whole file. Each sequence is tracked to the end of the file to give a representative count of the overall duplication level.

        The duplication detection requires an exact sequence match over the whole length of the sequence. Any reads over 75bp in length are truncated to 50bp for this analysis.

        Created with MultiQC

        Sequence Quality Histograms

        The mean quality value across each base position in the read.

        To enable multiple samples to be plotted on the same graph, only the mean quality scores are plotted (unlike the box plots seen in FastQC reports).

        Taken from the FastQC help:

        The y-axis on the graph shows the quality scores. The higher the score, the better the base call. The background of the graph divides the y axis into very good quality calls (green), calls of reasonable quality (orange), and calls of poor quality (red). The quality of calls on most platforms will degrade as the run progresses, so it is common to see base calls falling into the orange area towards the end of a read.

        Created with MultiQC

        Per Sequence Quality Scores

        The number of reads with average quality scores. Shows if a subset of reads has poor quality.

        From the FastQC help:

        The per sequence quality score report allows you to see if a subset of your sequences have universally low quality values. It is often the case that a subset of sequences will have universally poor quality, however these should represent only a small percentage of the total sequences.

        Created with MultiQC

        Per Base Sequence Content

        The proportion of each base position for which each of the four normal DNA bases has been called.

        To enable multiple samples to be shown in a single plot, the base composition data is shown as a heatmap. The colours represent the balance between the four bases: an even distribution should give an even muddy brown colour. Hover over the plot to see the percentage of the four bases under the cursor.

        To see the data as a line plot, as in the original FastQC graph, click on a sample track.

        From the FastQC help:

        Per Base Sequence Content plots out the proportion of each base position in a file for which each of the four normal DNA bases has been called.

        In a random library you would expect that there would be little to no difference between the different bases of a sequence run, so the lines in this plot should run parallel with each other. The relative amount of each base should reflect the overall amount of these bases in your genome, but in any case they should not be hugely imbalanced from each other.

        It's worth noting that some types of library will always produce biased sequence composition, normally at the start of the read. Libraries produced by priming using random hexamers (including nearly all RNA-Seq libraries) and those which were fragmented using transposases inherit an intrinsic bias in the positions at which reads start. This bias does not concern an absolute sequence, but instead provides enrichement of a number of different K-mers at the 5' end of the reads. Whilst this is a true technical bias, it isn't something which can be corrected by trimming and in most cases doesn't seem to adversely affect the downstream analysis.

        Click a sample row to see a line plot for that dataset.
        Rollover for sample name
        Position: -
        %T: -
        %C: -
        %A: -
        %G: -

        Per Sequence GC Content

        The average GC content of reads. Normal random library typically have a roughly normal distribution of GC content.

        From the FastQC help:

        This module measures the GC content across the whole length of each sequence in a file and compares it to a modelled normal distribution of GC content.

        In a normal random library you would expect to see a roughly normal distribution of GC content where the central peak corresponds to the overall GC content of the underlying genome. Since we don't know the GC content of the genome the modal GC content is calculated from the observed data and used to build a reference distribution.

        An unusually shaped distribution could indicate a contaminated library or some other kinds of biased subset. A normal distribution which is shifted indicates some systematic bias which is independent of base position. If there is a systematic bias which creates a shifted normal distribution then this won't be flagged as an error by the module since it doesn't know what your genome's GC content should be.

        Created with MultiQC

        Per Base N Content

        The percentage of base calls at each position for which an N was called.

        From the FastQC help:

        If a sequencer is unable to make a base call with sufficient confidence then it will normally substitute an N rather than a conventional base call. This graph shows the percentage of base calls at each position for which an N was called.

        It's not unusual to see a very low proportion of Ns appearing in a sequence, especially nearer the end of a sequence. However, if this proportion rises above a few percent it suggests that the analysis pipeline was unable to interpret the data well enough to make valid base calls.

        Created with MultiQC

        Sequence Length Distribution

        The distribution of fragment sizes (read lengths) found. See the FastQC help

        Created with MultiQC

        Sequence Duplication Levels

        The relative level of duplication found for every sequence.

        From the FastQC Help:

        In a diverse library most sequences will occur only once in the final set. A low level of duplication may indicate a very high level of coverage of the target sequence, but a high level of duplication is more likely to indicate some kind of enrichment bias (e.g. PCR over amplification). This graph shows the degree of duplication for every sequence in a library: the relative number of sequences with different degrees of duplication.

        Only sequences which first appear in the first 100,000 sequences in each file are analysed. This should be enough to get a good impression for the duplication levels in the whole file. Each sequence is tracked to the end of the file to give a representative count of the overall duplication level.

        The duplication detection requires an exact sequence match over the whole length of the sequence. Any reads over 75bp in length are truncated to 50bp for this analysis.

        In a properly diverse library most sequences should fall into the far left of the plot in both the red and blue lines. A general level of enrichment, indicating broad oversequencing in the library will tend to flatten the lines, lowering the low end and generally raising other categories. More specific enrichments of subsets, or the presence of low complexity contaminants will tend to produce spikes towards the right of the plot.

        Created with MultiQC

        Overrepresented sequences by sample

        The total amount of overrepresented sequences found in each library.

        FastQC calculates and lists overrepresented sequences in FastQ files. It would not be possible to show this for all samples in a MultiQC report, so instead this plot shows the number of sequences categorized as overrepresented.

        Sometimes, a single sequence may account for a large number of reads in a dataset. To show this, the bars are split into two: the first shows the overrepresented reads that come from the single most common sequence. The second shows the total count from all remaining overrepresented sequences.

        From the FastQC Help:

        A normal high-throughput library will contain a diverse set of sequences, with no individual sequence making up a tiny fraction of the whole. Finding that a single sequence is very overrepresented in the set either means that it is highly biologically significant, or indicates that the library is contaminated, or not as diverse as you expected.

        FastQC lists all the sequences which make up more than 0.1% of the total. To conserve memory only sequences which appear in the first 100,000 sequences are tracked to the end of the file. It is therefore possible that a sequence which is overrepresented but doesn't appear at the start of the file for some reason could be missed by this module.

        84 samples had less than 1% of reads made up of overrepresented sequences

        Top overrepresented sequences

        Top overrepresented sequences across all samples. The table shows 20 most overrepresented sequences across all samples, ranked by the number of samples they occur in.

        Showing 8/8 rows and 3/3 columns.
        Overrepresented sequenceReportsOccurrences% of all reads
        TCCCGTATCGAAGGCCTTTTTGGACAGGTGGTGTGTGGTGGCCTTGGTAT
        17
        687970
        0.0256%
        TCACATGCCTATCATATAGTAAAACCCAGCCCATGACCCCTAACAGGGGC
        10
        407874
        0.0152%
        TCCTCACCCGGCCCGGACACGGACAGGATTGACAGATTGATAGCTCTTTC
        2
        137726
        0.0051%
        TCCTGCCAGTAGCATATGCTTGTCTCAAAGATTAAGCCATGCATGTCTAA
        1
        64727
        0.0024%
        TGTGAAAGATGAGCTGGAGGACCGCAATAGGGGTAGGTCCCCTGTGGAAA
        1
        45869
        0.0017%
        TGTCGGCATGTATTAGCTCTAGAATTACCACAGTTATCCAAGTAGGAGAG
        1
        34145
        0.0013%
        TGGCAGACGTTCGAATGGGTCGTCGCCGCCACGGGGGGCGTGCGATCGGC
        1
        33911
        0.0013%
        TGGGGGCTTCAATCGGGAGTACTACTCGATTGTCAACGTCAAGGAGTCGC
        1
        30502
        0.0011%

        Adapter Content

        The cumulative percentage count of the proportion of your library which has seen each of the adapter sequences at each position.

        Note that only samples with ≥ 0.1% adapter contamination are shown.

        There may be several lines per sample, as one is shown for each adapter detected in the file.

        From the FastQC Help:

        The plot shows a cumulative percentage count of the proportion of your library which has seen each of the adapter sequences at each position. Once a sequence has been seen in a read it is counted as being present right through to the end of the read so the percentages you see will only increase as the read length goes on.

        Created with MultiQC

        Status Checks

        Status for each FastQC section showing whether results seem entirely normal (green), slightly abnormal (orange) or very unusual (red).

        FastQC assigns a status for each section of the report. These give a quick evaluation of whether the results of the analysis seem entirely normal (green), slightly abnormal (orange) or very unusual (red).

        It is important to stress that although the analysis results appear to give a pass/fail result, these evaluations must be taken in the context of what you expect from your library. A 'normal' sample as far as FastQC is concerned is random and diverse. Some experiments may be expected to produce libraries which are biased in particular ways. You should treat the summary evaluations therefore as pointers to where you should concentrate your attention and understand why your library may not look random and diverse.

        Specific guidance on how to interpret the output of each module can be found in the relevant report section, or in the FastQC help.

        In this heatmap, we summarise all of these into a single heatmap for a quick overview. Note that not all FastQC sections have plots in MultiQC reports, but all status checks are shown in this heatmap.

        Created with MultiQC

        Salmon

        Quantifies expression of transcripts using RNA-seq data.URL: https://combine-lab.github.io/salmonDOI: 10.1038/nmeth.4197

        Created with MultiQC

        Sample relationships

        Plots interrogating sample relationships, based on final count matrices.

        SALMON DESeq2 sample similarity

        is generated from clustering by Euclidean distances between DESeq2 rlog values for each sample in the deseq2_qc.r script.

        Created with MultiQC

        SALMON DESeq2 PCA plot

        PCA plot between samples in the experiment. These values are calculated using DESeq2 in the deseq2_qc.r script.

        Created with MultiQC

        Software Versions

        Software Versions lists versions of software tools extracted from file contents.

        GroupSoftwareVersion
        CUSTOM_GETCHROMSIZESgetchromsizes1.21
        CUSTOM_TX2GENEpython3.10.4
        DESEQ2_QC_PSEUDObioconductor-deseq21.28.0
        r-base4.0.3
        FASTQCfastqc0.12.1
        FQ_LINTfq0.12.0 (2024-07-08)
        FQ_SUBSAMPLEfq0.12.0 (2024-07-08)
        GTF2BEDperl5.26.2
        GTF_FILTERpython3.9.5
        GUNZIP_FASTAgunzip1.13
        GUNZIP_GTFgunzip1.13
        MAKE_TRANSCRIPTS_FASTArsem1.3.1
        star2.7.10a
        SALMON_QUANTsalmon1.10.3
        SE_GENE_UNIFIEDbioconductor-summarizedexperiment1.32.0
        SE_TRANSCRIPT_UNIFIEDbioconductor-summarizedexperiment1.32.0
        TRIMGALOREcutadapt4.9
        pigz2.8
        trimgalore0.6.10
        TXIMETA_TXIMPORTbioconductor-tximeta1.20.1
        WorkflowNextflow25.04.6
        nf-core/rnaseqv3.21.0-g9738a2d

        nf-core/rnaseq Methods Description

        Suggested text and references to use when describing pipeline usage within the methods section of a publication.URL: https://github.com/nf-core/rnaseq

        Methods

        Data was processed using nf-core/rnaseq v3.21.0 (doi: 10.5281/zenodo.1400710) of the nf-core collection of workflows (Ewels et al., 2020), utilising reproducible software environments from the Bioconda (Grüning et al., 2018) and Biocontainers (da Veiga Leprevost et al., 2017) projects.

        The pipeline was executed with Nextflow v25.04.6 (Di Tommaso et al., 2017) with the following command:

        nextflow run nf-core/rnaseq -profile unavcluster -params-file params_rnaseq.yaml -c hpc.config

        References

        • Di Tommaso, P., Chatzou, M., Floden, E. W., Barja, P. P., Palumbo, E., & Notredame, C. (2017). Nextflow enables reproducible computational workflows. Nature Biotechnology, 35(4), 316-319. doi: 10.1038/nbt.3820
        • Ewels, P. A., Peltzer, A., Fillinger, S., Patel, H., Alneberg, J., Wilm, A., Garcia, M. U., Di Tommaso, P., & Nahnsen, S. (2020). The nf-core framework for community-curated bioinformatics pipelines. Nature Biotechnology, 38(3), 276-278. doi: 10.1038/s41587-020-0439-x
        • Grüning, B., Dale, R., Sjödin, A., Chapman, B. A., Rowe, J., Tomkins-Tinch, C. H., Valieris, R., Köster, J., & Bioconda Team. (2018). Bioconda: sustainable and comprehensive software distribution for the life sciences. Nature Methods, 15(7), 475–476. doi: 10.1038/s41592-018-0046-7
        • da Veiga Leprevost, F., Grüning, B. A., Alves Aflitos, S., Röst, H. L., Uszkoreit, J., Barsnes, H., Vaudel, M., Moreno, P., Gatto, L., Weber, J., Bai, M., Jimenez, R. C., Sachsenberg, T., Pfeuffer, J., Vera Alvarez, R., Griss, J., Nesvizhskii, A. I., & Perez-Riverol, Y. (2017). BioContainers: an open-source and community-driven framework for software standardization. Bioinformatics (Oxford, England), 33(16), 2580–2582. doi: 10.1093/bioinformatics/btx192
        Notes:
        • The command above does not include parameters contained in any configs or profiles that may have been used. Ensure the config file is also uploaded with your publication!
        • You should also cite all software used within this run. Check the "Software Versions" of this report to get version information.

        nf-core/rnaseq Workflow Summary

        Input/output options

        input
        samplesheet_eocrc.csv
        multiqc_title
        crc-rna-seq-salmon
        outdir
        results

        Reference genome options

        fasta
        data/genomes/GRCh38/GRCh38.primary_assembly.genome.fa.gz
        gencode
        true
        gtf
        data/genomes/GRCh38/gencode.v49.primary_assembly.annotation.gtf.gz
        igenomes_ignore
        true
        salmon_index
        data/genomes/GRCh38/genome_gencode/index/salmon

        UMI options

        umi_discard_read
        0

        Alignment options

        pseudo_aligner
        salmon

        Process skipping options

        skip_alignment
        true

        Generic options

        trace_report_suffix
        2025-11-29_16-24-20

        Core Nextflow options

        configFiles
        /home/samarquez/.nextflow/assets/nf-core/rnaseq/nextflow.config, /beegfs/home/samarquez/tfm-rnaseq/master-bioinformatics/nextflow-pipelines/nf-core-rnaseq/nf-core-rnaseq-salmon-pe/hpc.config
        containerEngine
        singularity
        launchDir
        /beegfs/home/samarquez/tfm-rnaseq/master-bioinformatics/nextflow-pipelines/nf-core-rnaseq/nf-core-rnaseq-salmon-pe
        profile
        unavcluster
        projectDir
        /home/samarquez/.nextflow/assets/nf-core/rnaseq
        revision
        master
        runName
        festering_poitras
        userName
        samarquez
        workDir
        /beegfs/home/samarquez/tfm-rnaseq/master-bioinformatics/nextflow-pipelines/nf-core-rnaseq/nf-core-rnaseq-salmon-pe/work