Unconfigured Ad

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • marianaboroni
    Junior Member
    • Feb 2011
    • 5

    Problem with DEXSeq read.HTSeqCounts

    Hi!
    I'm trying to use the pipeline tophat2 -> HTSEq -> DEXSeq, but I'm stuck on the DEXSEq workflow!

    Here is what I did:

    1) I ran TopHat2 using a junc file:
    tophat2 -o tophat_out -i 10 -I 30000 -p 8 --library-type fr-unstranded -j combined.juncs -G my.gff --transcriptomeindex=transcriptome_data chr.fa myreads_1.fastq myreads_2.fastq
    2) I converted bam to the sam file:
    samtools sort -n accepted_hits.bam accepted_hits.nsorted
    samtools view accepted_hits.nsorted.bam > ./accepted_hits.nsorted.sam
    3) Then I produced the count table using htseq-count
    htseq-count -i ID accepted_hits.nsorted.sam my.gff -q --stranded=yes > count_HTSeq_exons.txt
    4)Now I'm trying to use the DEXSeq package to test differential use of exons

    #My code in R
    library("DEXSeq")
    samples = data.frame(
    condition = factor(c("sl","all","all","all","all")),
    replicate = factor(c(1:1,1:4)),
    type = c("single-read", "paired-end", "paired-end", "paired-end", "paired-end"),
    row.names = factor(c("cercaria_SL_Trapping_count_HTSeq_exons","Todos_cercaria_ERR022872_count_HTSeq_exons", "Todos_cercaria_ERR022875_count_HTSeq_exons", "Todos_cercaria_ERR022877_count_HTSeq_exons", "Todos_cercaria_ERR022878_count_HTSeq_exons")),
    stringsAsFactors = TRUE,
    check.names = FALSE
    )
    annotationfile = file.path("./GFF/v5.07.08.12.chado.HTSeq.gff")
    ecs = read.HTSeqCounts(countfiles = paste(rownames(samples), "txt", sep=".") , design = samples, flattenedfile = annotationfile)
    sampleNames(ecs) = rownames(samples)
    But then I get an error: Erro em x[[i]] : índice fora de limites

    If I try the last command without the GFF file, the object ecs is created without problems, what makes me think that the problem is with my GFF file, the same I used with the HTSeq-count.

    Here is a piece of my gff file:
    ##gff-version 3
    ##sequence-region Schisto_mansoni.Chr_1 1 65476681
    Schisto_mansoni.Chr_1 chado contig 1 19825 . + . ID=contig_14209;Name=null;
    Schisto_mansoni.Chr_1 chado gene 11159 12750 . + . ID=Smp_186980;
    Schisto_mansoni.Chr_1 chado exon 11159 11220 . + 0 ID=Smp_186980.1:exon:1;Parent=Smp_186980.1;
    Schisto_mansoni.Chr_1 chado exon 12411 12750 . + 0 ID=Smp_186980.1:exon:2;Parent=Smp_186980.1;
    Schisto_mansoni.Chr_1 chado mRNA 11159 12750 . + . ID=Smp_186980.1;Parent=Smp_186980;
    Schisto_mansoni.Chr_1 chado polypeptide 11159 12750 . + . ID=Smp_186980.1ep;Derives_from=Smp_186980.1;timelastmodified=14.10.2011+12:49:04+BST;feature_id=23195294;
    Schisto_mansoni.Chr_1 chado gene 16927 17315 . + . ID=Smp_197050;
    Schisto_mansoni.Chr_1 chado exon 16927 17082 . + 0 ID=Smp_197050.1:exon:1;Parent=Smp_197050.1;
    Schisto_mansoni.Chr_1 chado exon 17286 17315 . + 0 ID=Smp_197050.1:exon:2;Parent=Smp_197050.1;
    Schisto_mansoni.Chr_1 chado polypeptide 16927 17315 . + . ID=Smp_197050.1ep;Derives_from=Smp_197050.1;colour=2;timelastmodified=14.10.2011+12:50:09+BST;feature_id=23195325;
    Schisto_mansoni.Chr_1 chado mRNA 16927 17315 . + . ID=Smp_197050.1;Parent=Smp_197050;
    Schisto_mansoni.Chr_1 chado gap 19826 20025 . + . ID=Schisto_mansoni.Chr_1.embl:gap:19825-20025;
    Schisto_mansoni.Chr_1 chado contig 20026 60973 . + . ID=contig_14210;Name=null;
    Schisto_mansoni.Chr_1 chado gene 51849 114890 . + . ID=Smp_160500;
    Schisto_mansoni.Chr_1 chado exon 51849 51861 . + 0 ID=Smp_160500.1:exon:1;Parent=Smp_160500.1;
    Schisto_mansoni.Chr_1 chado exon 51901 51987 . + 0 ID=Smp_160500.1:exon:2;Parent=Smp_160500.1;
    Schisto_mansoni.Chr_1 chado exon 52024 52416 . + 0 ID=Smp_160500.1:exon:3;Parent=Smp_160500.1;
    Schisto_mansoni.Chr_1 chado exon 52448 52679 . + 0 ID=Smp_160500.1:exon:4;Parent=Smp_160500.1;
    Schisto_mansoni.Chr_1 chado exon 52715 52802 . + 0 ID=Smp_160500.1:exon:5;Parent=Smp_160500.1;

    Any sugestion??

    Thanks!

Latest Articles

Collapse

  • 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
  • SEQadmin2
    From Collection to Sequencing: Why Sample Preparation and Preservation Define Sequencing Data
    by SEQadmin2


    Data variability is still an issue in sequencing technologies despite the advances in reproducibility and accuracy of these platforms. But the problem does not originate in the sequencing itself, but in the previous steps, before the sample reaches the sequencer.


    The first step is collection, followed by preservation and sample preparation for analysis. Most scientists overlook those steps, but not being careful might just be skewing the experiment’s results.
    ...
    06-02-2026, 10:05 AM

ad_right_rmr

Collapse

News

Collapse

Topics Statistics Last Post
Started by SEQadmin2, 06-17-2026, 06:09 AM
0 responses
40 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 06-09-2026, 11:58 AM
0 responses
102 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 06-05-2026, 10:09 AM
0 responses
123 views
0 reactions
Last Post SEQadmin2  
Started by SEQadmin2, 06-04-2026, 08:59 AM
0 responses
114 views
0 reactions
Last Post SEQadmin2  
Working...