Questions tagged [coverage]

When referring to the coverage of a base in a reference genome, the number of reads covering that base in an alignment. When referring to the coverage of a genome in a sequencing experiment, the average number of times that a base was sequenced. = total number of sequenced bases / genome size. For example, a 100x coverage means that each base was sequenced on average 100 times. For the human genome, that would be ~ 300 Gigabases.

Filter by
Sorted by
Tagged with
4
votes
1answer
262 views

Calculating average coverage for .bam files (sequence data)

(Full discolosure that this is my first time working with sequence data, and with the bash scripting.) I need to calculate the average coverage for any .bam file. After some searching I wrote the ...
1
vote
0answers
38 views

Analyzing a blast result of NGS data

I am analyzing BLAST results from total RNA NGS, pair ends. This BLAST results was performed against the ssRNA virus database download from NCBI. I filtered those read data whose paired ends ...
2
votes
1answer
71 views

Bedtools wrongly indicates zero coverage

I have a BAM file produced using BWA-MEM and I need to calculate the coverage of each exon in this sequencing. I tried using this command: ...
1
vote
1answer
34 views

how to calculate coverage of each base of mapped reads?

I have a RNA aligned file without any header info. I need to calculate the coverage of each mapped base for per chromosome. Is it possible to do it with perl ? ...
1
vote
0answers
18 views

How to choose reference to calculate coverage of WGS of organism that has high intra-species variation?

Calculation of coverage involves mapping reads with a reference and depending on the choice of reference we can get very different result. If a species has a genome that has very low size variation ...
1
vote
0answers
94 views

bedtools coverage - Report the depth at each position in each A feature

I am using bedtools coverage to compute the sequencing depth at every positions of a chromosome but it didn't work as I expected. Instead it reported 0 coverage at every positions. This is how I did ...
1
vote
1answer
33 views

Metagenomic shotgun data with internal control

For 24 human stool samples I have metagenomic shotgun reads from an Illumina platform. The reads were filtered and mapped against a bacterial species library and specific maps to species were kept and ...
2
votes
1answer
129 views

Coverage required

I was came across a problem during an exercise in a book and I don't really know how to solve it. I feel like something's missing. "coverage, c = $NL/G$ (N=number of reads, L=read length, G=genome ...
2
votes
2answers
72 views

How to best detect the “peaks” in RNA-seq data that are not assigned to any gene?

I encountered that many reads from single-cell RNA seq data were lost in the analysis because not assigned to any gene (genome: galgal6). I am trying to find an approach than could give me all the "...
2
votes
1answer
97 views

How to take into account alternative bwa mem mapping when computing coverage

when mapping short reads with bwa mem, if a read has alternative mapping positions they are reported by bwa mem in the X0 and XA tags. Now, let's say I want to compute the coverage of my bam file. ...
1
vote
1answer
35 views

Total read count of shotgun affected by few highly abundant sequences

I am building statistical models to analyse output from Illumina shotgun sequencing (HiSeq 4000) on stool samples (but RNA-seq data should behave similarily). The raw counts are a statistical sample ...
1
vote
2answers
74 views

Extract mapping coverage from GTF files

I am doing paired end RNA-seq analysis. I used STAR mapper and then StringTie for getting quantification of my data. After successfully running StringTie, I got .gtf...
4
votes
3answers
564 views

How can I calculate coverage at single bases using a bam file?

I'm looking for a way to input a vcf or bed file (with specific base positions) and a bam file, and get the coverage at each base position (ie single base bins) using the bam file. I also want the ...
1
vote
0answers
102 views

CollectHsMetrics base coverage output has overlapping targets

I am trying to get base coverage information, and am using the --PER_BASE_COVERAGE output from Picard tools to get a text file of base level coverage. However, some ...
4
votes
2answers
297 views

Plotting coverage of annotation over collection of region

I'm trying to plot "meta" coverage of annotation: i.e. features (eg. gene class) over certain regions. It is similar to read coverage plots over gene body, except my input is two bed files (both in ...
1
vote
0answers
173 views

bedtools single-nucleotide coverage in BED-specified regions for multiple BAMs

I have a BED6 (BED + name, score, strand info) file that defines some regions of interest. I also have a set of BAMs corresponding to different samples. I would like to obtain output similar to <...
6
votes
4answers
1k views

Double-counting coverage of overlapped read pairs

EDIT: I do not want to make any modifications to the mapped reads, I simply want to ignore one read in a read pair if they overlap the same region. I used samtools depth to calculate the depth of ...
1
vote
1answer
86 views

How to calculate AUC in coverage graph

Is there a way to calculate the area under a curve in a coverage graph? Thank you in advance. EDIT: I'd like to calculate the AUC per strand per gene in a coverage graph. I have two wig files (...
6
votes
1answer
112 views

GATK documentation for required depth to reliably call heterozygous mutation in diploid organism?

I'm looking for official GATK documentation (or a recent manuscript) that defines a general recommendation/requirement for sequencing depth to reliably call a heterozygous point mutation in a diploid ...
1
vote
1answer
55 views

How many reads do I need for hybrid assembly

I have Illumina and PacBio reads and I would like to use dbg2olc for hybrid assembly. Part of dbg2olc is SelectLongestReads which select reads that sum to ...
3
votes
1answer
217 views

How many reads do I need to cover the entire genome?

Suppose my genome is 3 million bases and that my reads are 100 nucleotide long. I need to know how many reads I need to cover the entire genome. I start from using the equation $C = \frac{N \cdot L}{...
7
votes
1answer
757 views

Coverage calculation: long reads (RNA-seq)

Say your aim is to calculate the coverage of an RNA-seq experiment generated with long-read sequencing (so, uneven read length). Up to now, I relied on the Lander/Waterman equation: $$C = L*N / G$$...
7
votes
1answer
168 views

How to calculate overall reference coverage with MUMmer?

Is the MUMmer suite capable of calculating reference sequence coverage statistics for all query sequences collectively? It would be possible to achieve by parsing the output of ...
3
votes
1answer
1k views

Counts obtained by featureCounts seem much less than observed coverage

I have surprisingly low counts when running featureCounts on some (single-end) RNA-seq data mapped on C. elegans genome using ...