Questions tagged [bwa]
bwa (Burrows-Wheeler Aligner) is a software for aligning reads obtained with Next Generation Sequencing.
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Obtaining uniquely mapped reads from BWA mem alignment
This is based on a question from betsy.s.collins on BioStars. The original post can be found here.
Does anyone have any suggestions for other tags or filtering steps on BWA-generated BAM files that ...
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Difference between BWA-backtrack and BWA-MEM
Many of my colleagues recommend I use BWA-MEM instead of regular old BWA. The problem is I don't understand why and reading the BWA man page doesn't seem to help the matter.
What is the difference ...
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Why most aligners do not output the "X" CIGAR operation?
As I read the SAM spec, the "X" CIGAR operator represents a mismatch. This seems useful as we can know where are the mismatches without looking at the reference genome. However, many popular aligners ...
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How BWA generate index files?
I need to know how BWA generate bw and sa in less memory usage. I didn't find details in the original paper. Do they save all rotations temporary ? I need to know do BWA stores all rotations so that ...
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Why is bwa-mem the standard algorithm when using bwa?
The industry standard for aligning short reads seems to be bwa-mem. However, in my tests I have seen that using bwa backtrack (bwa-aln + bwa-sampe + bwa-samse) performs better. It is slightly slower, ...
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How does the BWA-MEM algorithm assign its mapping qualities?
Is there any resource (paper, blogpost, Github gist, etc.) describing the BWA-MEM algorithm for assigning mapping qualities? I vaguely remember that I have somewhere seen a formula for SE reads, which ...
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Library for computing BWT-based alignments
I am writing a software tool to which I would like to add the ability to compute alignments using the efficient Burrows-Wheeler Transform (BWT) approach made popular by tools such as BWA and Bowtie. ...
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Mark BWA-SW split alignments in output for long reads
Is there a way to remove split alignments of single-end long reads from BWA-SW output? BWA-MEM has an option to include or flag split alignments in the result, but it seems BWA-SW method include them ...
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Samtools Index: Chromosome Blocks not Continuous
I am working with short-read whole-genome sequences from the NCBI's SRA. I have aligned and sorted all of my short-read sequences and am attempting to index each sequence into .bai format using ...
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Variant calling for a subset of genes using whole gneome sequencing data
I have few 100 raw fastq files from whole-genome sequencing data and I would like to map these files to a set of genes only (and not whole genome) so as to find SNP's associated with them. Can anyone ...
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