Seqanswers Leaderboard Ad

Collapse

Announcement

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

  • dpryan
    replied
    I'd have to recheck the strandedness settings, maybe you just need "-s reverse" to match your library type.

    Leave a comment:


  • gandalf886
    replied
    Got most mapped reads counted if I specify -s no, but the library was made using a strand-specific protocol and mapped using tophat in --library-type fr-firststrand mode. Don't know why.

    Leave a comment:


  • dpryan
    replied
    Have a look at things in IGV or use the -o option to track what's happening to reads that aren't getting counted but you think should be.

    Leave a comment:


  • gandalf886
    started a topic htseq-count low count problem

    htseq-count low count problem

    Hi guys,

    I am looking at some RNA-seq data using DEseq2, before this I need to get a count table for each gene.

    here is what i have done:

    mapped the stranded, paired-end reads to transcriptome using tophat2:
    Code:
    tophat -p 12 -r 60 -o $out --transcriptome-only --no-novel-juncs --no-coverage-search --library-type fr-firststrand --transcriptome-ind
    ex=$known $hg19 lane1.1.repaa_val_1.fq lane1.2.repaa_val_2.fq
    I got about 6.5 million mapped pairs, which is about 50% of the input reads.

    then i took the mapped reads and count them against a gtf table

    Code:
    htseq-count -f bam -r pos -t exon -i gene_id accepted_hits.bam hg19.gtf > accepted_hits.bam.counts
    I got 0.4 million reads counted into the table and the number of no feature reads is about 13 million.

    I tried to sort the bam files using samtools and use -r name option in the htseq-count line but it also didn't work.

    this is how the gtf file look like
    Code:
    chr1	unknown	exon	11874	12227	.	+	.	gene_id "DDX11L1"; gene_name "DDX11L1"; transcript_id "NR_046018"; tss_id "TSS14844";
    chr1	unknown	exon	12613	12721	.	+	.	gene_id "DDX11L1"; gene_name "DDX11L1"; transcript_id "NR_046018"; tss_id "TSS14844";
    chr1	unknown	exon	13221	14409	.	+	.	gene_id "DDX11L1"; gene_name "DDX11L1"; transcript_id "NR_046018"; tss_id "TSS14844";
    chr1	unknown	exon	14362	14829	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	14970	15038	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	15796	15947	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	16607	16765	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	16858	17055	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	17233	17368	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	17606	17742	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	17915	18061	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	18268	18366	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	24738	24891	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	29321	29370	.	-	.	gene_id "WASH7P"; gene_name "WASH7P"; transcript_id "NR_024540"; tss_id "TSS7514";
    chr1	unknown	exon	34611	35174	.	-	.	gene_id "FAM138A"; gene_name "FAM138A"; transcript_id "NR_026818_1"; tss_id "TSS8403";
    chr1	unknown	exon	34611	35174	.	-	.	gene_id "FAM138F"; gene_name "FAM138F"; transcript_id "NR_026820_1"; tss_id "TSS8403";
    chr1	unknown	exon	35277	35481	.	-	.	gene_id "FAM138A"; gene_name "FAM138A"; transcript_id "NR_026818_1"; tss_id "TSS8403";
    chr1	unknown	exon	35277	35481	.	-	.	gene_id "FAM138F"; gene_name "FAM138F"; transcript_id "NR_026820_1"; tss_id "TSS8403";
    chr1	unknown	exon	35721	36081	.	-	.	gene_id "FAM138A"; gene_name "FAM138A"; transcript_id "NR_026818_1"; tss_id "TSS8403";
    chr1	unknown	exon	35721	36081	.	-	.	gene_id "FAM138F"; gene_name "FAM138F"; transcript_id "NR_026820_1"; tss_id "TSS8403";
    chr1	unknown	CDS	69091	70005	.	+	0	gene_id "OR4F5"; gene_name "OR4F5"; p_id "P1230"; transcript_id "NM_001005484"; tss_id "TSS14428";
    chr1	unknown	exon	69091	70008	.	+	.	gene_id "OR4F5"; gene_name "OR4F5"; p_id "P1230"; transcript_id "NM_001005484"; tss_id "TSS14428";
    chr1	unknown	start_codon	69091	69093	.	+	.	gene_id "OR4F5"; gene_name "OR4F5"; p_id "P1230"; transcript_id "NM_001005484"; tss_id "TSS14428";
    chr1	unknown	stop_codon	70006	70008	.	+	.	gene_id "OR4F5"; gene_name "OR4F5"; p_id "P1230"; transcript_id "NM_001005484"; tss_id "TSS14428";
    Any ideas? thanks

Latest Articles

Collapse

  • seqadmin
    Essential Discoveries and Tools in Epitranscriptomics
    by seqadmin




    The field of epigenetics has traditionally concentrated more on DNA and how changes like methylation and phosphorylation of histones impact gene expression and regulation. However, our increased understanding of RNA modifications and their importance in cellular processes has led to a rise in epitranscriptomics research. “Epitranscriptomics brings together the concepts of epigenetics and gene expression,” explained Adrien Leger, PhD, Principal Research Scientist...
    04-22-2024, 07:01 AM
  • seqadmin
    Current Approaches to Protein Sequencing
    by seqadmin


    Proteins are often described as the workhorses of the cell, and identifying their sequences is key to understanding their role in biological processes and disease. Currently, the most common technique used to determine protein sequences is mass spectrometry. While still a valuable tool, mass spectrometry faces several limitations and requires a highly experienced scientist familiar with the equipment to operate it. Additionally, other proteomic methods, like affinity assays, are constrained...
    04-04-2024, 04:25 PM

ad_right_rmr

Collapse

News

Collapse

Topics Statistics Last Post
Started by seqadmin, Yesterday, 08:47 AM
0 responses
15 views
0 likes
Last Post seqadmin  
Started by seqadmin, 04-11-2024, 12:08 PM
0 responses
60 views
0 likes
Last Post seqadmin  
Started by seqadmin, 04-10-2024, 10:19 PM
0 responses
60 views
0 likes
Last Post seqadmin  
Started by seqadmin, 04-10-2024, 09:21 AM
0 responses
54 views
0 likes
Last Post seqadmin  
Working...
X