Picard Matequery Slows Process To A Crawl
I'm looking to iterate through an indexed BAM file using picard and perform various tests on both a read and it's mate. For some I would need the full SAMRecord for the mate so I can't just use the...
View ArticleAnalyzing Older Illumina Paired-End Data
Hi all, I've got some reads from mid-2010 that I'd like to re-align. I'm not sure how best to proceed. These are from a Illumina Genome Analyzer IIx. They're 40-bp, paired-end. Here's what the text...
View ArticleCounting sense reads in bacterial paired-end RNA-seq data
Hi, I'm trying to count reads mapping to sense strand. I have doubts which counts file I should chose from this pipeline. I think is "plate_R.counts" because has more reads counted in total. Am I...
View ArticleAligning Paired-End Reads In Single-End Mode
Hello,I have a question on how to align paired-end reads.In cases of very large fastq files, which make aligners like TopHat crash in a server with limited memory in RAM, I have seen people align one...
View ArticleIdentifying mutations from Paired-End Sequencing data
Hello! I'm trying to get mutations from paired-end sequenced reads aligned with BWA using SamTools. Coverage is about 16,000. Generally it works fine, but in one fragment (TGGGC) i see that in reads...
View ArticlePair End Sequencing Problem
Dear all,I have a quick question on pair end sequencing. I used to work with Illumina without the pair end reads and I have dificulties to understand how the pair end reads work.In the "old" system you...
View ArticleBest way to map paired-end, uniquely mapped reads with Bowtie2?
This has come up before, but I have never been satisfied with, or completly understood, the answers. My issue is how can Bowtie2 be used to map uniquely mapping paired-end reads (Illumina) to a genome...
View ArticleDoes Order Within Read Pairs In Interleaved Files Matter?
I have now ended up with interleaved paired-end read files where the order of reads is not the same throughout the file, ie. sometimes the forward read is first, sometimes the reverse read is first,...
View ArticlePaired End Vs Single End Detection
Hi, I am wondering if anyone has a subroutine or function (hopefully in Perl or pseudocode) to detect whether a fastq file is a shuffled paired-end or not. I think I've seen a few different syntaxes on...
View ArticleSamtools Mpileup And Overlapping Paired-End Reads
I am using samtools mpileup to generate a pileup for paired-end RNA sequencing data. I am curious about how samtools handles pair mates whose read mappings overlap. With regard to the simple example...
View ArticleMerging Illumina Paired End Reads
Dear All,I have fastq a dataset containing forward and reverse sequences obtained through paired end module of Illumina platform. I am trying to merge these paired end reads. I have a query which I...
View ArticleRoche 454: How to know if reads are paired ?
Hi,Imagine a Fastq file generated from a Roche 454 platform. You have no information whatsoever about the protocol that what used. The header of the reads give no specific information, just random...
View ArticleCollect Read Pairs Where At Least One Read Is Mapped
I might word my initial question like another post, but I really have the opposite meaning, i think:Filtering multiple flags with SAMtoolsI am trying to remove paired-end reads from a .SAM file where...
View ArticleCoverage For Pair-End Rna-Seq, Extend Reads Or Not?
HI, all I have a question when computing region coverage of pair-end RNASeq data. As showed by the sketch map, when computing region coverage, whether I should use actually mapped reads or extended...
View ArticleUnderstanding Samtools Flagstat Output
The following is the output of samtools flagstat command on bam file (paired-end) generated after markDuplicate of Picards.7417232 + 0 in total (QC-passed reads + QC-failed reads) 287618 + 0 duplicates...
View ArticleTool: Trim Adapters Of Paired-End Reads (Fastq)
Trimming adapter sequences of paired-end experiments is sometimes a problem. If you clip the mates in two steps, it migh happen that you loose one mate, but not the corresponding one, resulting in two...
View ArticleHow To Determine If Library Is Strand-Specific
Hello all, this might be a very basic question but I gave it some thought and don't see a satisfactory answer.Let's say I have a FASTQ file from a sequencing experiment. How can one quickly determine...
View ArticleJoining Paired-End Illumina Raw Reads
I recently have amplicons sequenced (Illumina PE250) to investigate microbial community. I want to know what quality detection, and what kind of trims of raw reads by what programs should be performed...
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Trinity Question
Hi， I 'd like to use Trinity to analyze my strand-specific pair-end sequencing data (dUTP) and I am very confused about how to choose the argument. I got two reads files, _1.fa and _2.fa. For...
View ArticleTake A Subset Of A Fastq Paired-End Sample
Hi,I have two paired-end fastq compressed files coming from HiSeq RNA-SEq experiment, ie., pair.1.fastq.gz and pair.2.fastq.gz.The files are very large so I wanted to just take a few million/thousand...
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