A highly parallelized utility for variation statistics at per genome position.
Why perbase when so many other tools are out there? perbase leverages Rust's concurrency system to automagically parallelize over your input regions. This leads to orders of magnitude faster runtimes that scale with the compute resources that you have available. Additionally, perbase aims to be more accurate than other tools. E.g.: perbase counts DELs toward depth, bam-readcount does not, perbase does not count REF_SKIPs toward depth, sambamba does.
- build from source code by Cargo compiler
git clone https://github.com/Schaudge/perbase
cd perbase
cargo build --release- Download the static binary from release
https://github.com/Schaudge/perbase/releases/download/v0.9.1/perbase-linux-amd64
The base-depth tool walks over every position in the BAM/CRAM file and calculates the depth, as well as the number of each nucleotide at the given position. Additionally, it counts the numbers of Ins/Dels at each position.
The output columns are as follows:
| Column | Description |
|---|---|
| REF | The reference sequence name |
| POS | The position on the reference sequence |
| REF_BASE | The reference base at the position, column excluded if no reference was supplied |
| DEPTH | The total depth at the position SUM(A, C, T, G, DEL) |
| A | Total A nucleotides seen at this position |
| C | Total C nucleotides seen at this position |
| G | Total G nucleotides seen at this position |
| T | Total T nucleotides seen at this position |
| N | Total N nucleotides seen at this position |
| INS | Total insertions that start at the base to the right of this position |
| INS_MASTER_SEQ | The master frequent inserted sequence of insertions to the right of this position |
| INS_SEQ_COUNT | Total counts for the master frequent insertions to the right of this position |
| DEL | Total deletions covering this position |
| DEL_CONTEXT_SEQ | The master 20 bps context sequence of (long) deletions of this position |
| DEL_SEQ_COUNT | Total counts of above sequence of the master frequent (long) deletions of this position |
| REF_SKIP | Total reference skip operations covering this position |
| FAIL | Total reads failing filters that covered this position (their bases were not counted toward depth) |
| NEAR_MAX_DEPTH | Flag to indicate if this position came within 1% of the max depth specified |
perbase base-depth ./test/test.bamExample output
NAME REF POS REF_BASE DEPTH A C G T N INS INS_MASTER_SEQ INS_SEQ_COUNT DEL DEL_CONTEXT_SEQ DEL_SEQ_COUNT REF_SKIP FAIL NEAR_MAX_DEPTH
EGFR:exon19 7 55242464 T 1351 2 0 2 1337 0 0 0 0 0 0 0 false
EGFR:exon19 7 55242465 G 1356 2 3 1345 2 0 0 0 4 GAACCAACAT 182 0 0 false
EGFR:exon19 7 55242466 G 1361 0 1 1168 5 0 0 0 187 0 0 0 false
EGFR:exon19 7 55242467 A 1382 1195 0 0 0 0 0 0 187 0 0 0 false
EGFR:exon19 7 55242468 A 1386 1198 0 0 1 0 0 0 187 0 0 0 false
EGFR:exon19 7 55242469 T 1383 4 2 1 1189 0 0 0 187 0 0 0 false
EGFR:exon19 7 55242470 T 1401 2 1 0 1211 0 0 0 187 0 0 0 false
EGFR:exon19 7 55242471 A 1419 1229 0 2 1 0 0 0 187 0 0 0 false
EGFR:exon19 7 55242472 A 1442 1252 0 0 3 0 0 0 187 0 0 0 false
EGFR:exon19 7 55242473 G 1445 0 0 1258 0 0 0 0 187 0 0 0 false
EGFR:exon19 7 55242474 A 1439 1256 0 0 0 0 0 0 183 0 0 0 false
EGFR:exon19 7 55242475 G 1445 1 1 1441 2 0 0 0 0 0 0 0 false
EGFR:exon19 7 55242476 A 1448 1446 0 0 2 0 0 0 0 0 0 0 false
EGFR:exon19 7 55242477 A 1450 1450 0 0 0 0 0 0 0 0 0 0 false
EGFR:exon19 7 55242478 G 1452 0 187 1262 3 0 0 0 0 0 0 0 false
EGFR:exon19 7 55242479 C 1479 2 1475 1 0 1 0 0 0 0 0 0 false
EGFR:exon19 7 55242480 A 1481 1475 1 1 3 1 0 0 0 0 0 0 false
If the --mate-fix flag is passed, each position will first check if there are any mate overlaps and choose the mate with the hightest MAPQ, breaking ties by choosing the first mate that passes filters. Mates that are discarded are not counted toward FAIL or DEPTH.
If the --reference-fasta is supplied, the REF_BASE field will be filled in. The reference must be indexed an match the BAM/CRAM header of the input.
The output can be compressed and indexed as follows:
perbase base-depth -Z ./test/test.bam -o output.tsv.gz
tabix -S 1 -s 1 -b 2 -e 2 ./output.tsv.gz
# Query all positions overlapping region
tabix output.tsv.gz chr1:5-10convert base-depth out (uncompressed) into VCF format (only support complex long deletions currently, other cases were trivial!)
python3 script/convert_indels_vcf.py [base-depth out] [vcf result name] [sample id in VCF FORMAT field]Usage:
Calculate the depth at each base, per-nucleotide
USAGE:
perbase base-depth [FLAGS] [OPTIONS] <reads>
FLAGS:
-Z, --bgzip
Optionally bgzip the output
-h, --help
Prints help information
-k, --keep-zeros
Keep positions even if they have 0 depth
-m, --mate-fix
Fix overlapping mates counts, see docs for full details
-M, --skip-merging-intervals
Skip mergeing togther regions specified in the optional BED or BCF/VCF files.
**NOTE** If this is set it could result in duplicate output entries for regions that overlap. **NOTE** This
may cause issues with downstream tooling.
-V, --version
Prints version information
-z, --zero-base
Output positions as 0-based instead of 1-based
OPTIONS:
-B, --bcf-file <bcf-file>
A BCF/VCF file containing positions of interest. If specified, only bases from the given positions will be
reported on
-b, --bed-file <bed-file>
A BED file containing regions of interest. If specified, only bases from the given regions will be reported
on
-C, --channel-size-modifier <channel-size-modifier>
The fraction of a gigabyte to allocate per thread for message passing, can be greater than 1.0 [default:
0.15]
-c, --chunksize <chunksize>
The ideal number of basepairs each worker receives. Total bp in memory at one time is (threads - 2) *
chunksize [default: 1000000]
-L, --compression-level <compression-level>
The level to use for compressing output (specified by --bgzip) [default: 2]
-T, --compression-threads <compression-threads>
The number of threads to use for compressing output (specified by --bgzip) [default: 4]
-F, --exclude-flags <exclude-flags>
SAM flags to exclude, recommended 3848 [default: 0]
-f, --include-flags <include-flags>
SAM flags to include [default: 0]
-D, --max-depth <max-depth>
Set the max depth for a pileup. If a positions depth is within 1% of max-depth the `NEAR_MAX_DEPTH` output
field will be set to true and that position should be viewed as suspect [default: 2000000]
-Q, --min-base-quality-score <min-base-quality-score>
Minium base quality for a base to be counted toward [A, C, T, G]. If the base is less than the specified
quality score it will instead be counted as an `N`. If nothing is set for this no cutoff will be applied
-q, --min-mapq <min-mapq>
Minimum MAPQ for a read to count toward depth [default: 0]
-o, --output <output>
Output path, defaults to stdout
--ref-cache-size <ref-cache-size>
Number of Reference Sequences to hold in memory at one time. Smaller will decrease mem usage [default: 10]
-r, --ref-fasta <ref-fasta>
Indexed reference fasta, set if using CRAM
-t, --threads <threads>
The number of threads to use [default: 32]
ARGS:
<reads>
Input indexed BAM/CRAM to analyze
The only-depth tool walks over the input BAM/CRAM file and calculates the depth over all positions specified by either a BED file or in the BAM/CRAM header. Adjacent positions that have the same depth will be merged together to form a non-inclusive range (see example output).
There are two distinct modes that only-depth can run in, gated by the --fast-mode flag. When running in fast-mode, only depth over the area a read covers is only determined by the reads start and end postions, and no cigar related info is taken into account. --mate-fix may still be used in this mode, and areas where mates overlap will not be counted twice.
Without the --fast-mode flag, the depth at each position is determined in a manner similar to base-depth where DEL will count toward depth, but REF_SKIP will not. Additionally, any reads that fail the --exclude-flags will not be counted toward depth. Lastly, --mate-fix can be applied to avoid counting regions twice where mates may overlap.
Regarding mate fixes, perbase will make "fixes" based only on the counted regions in a read. For example, if you have a read that goes from "chr1:0-1000" with a CIGAR of "25M974N1M", and the mate aligns nicely at "chr1:45-70" with CIGAR "25M", the mate will count toward the depth over "chr1:45-74". This is in contrast to other tools that will reject the mate even though it overlaps a region of R1 that is not counted toward depth.
For the fastest possible output, use only-depth --fast-mode.
Note that it is possible that two adjacent positions may not merge if they fall at a --chunksize boundary. If this is an issue you can set the --chunksize to the size of the largest contig in question. At a future date this may be fixed or a post processing tool may be provided to fix it. For most use cases this should not be a problem. Additionally, you can pipe into merge-adjacent which will fix it as well. EX: perbase only-depth -m file.bam | perbase merge-adjacent > out.tsv.
Example output of perbase only-depth --mate-fix --zero-base ./test/test.bam:
REF POS END DEPTH
chr2 0 4 1
chr2 4 9 2
chr2 9 12 3
chr2 12 14 2
chr2 14 17 3
chr2 17 19 4
chr2 19 23 5
chr2 23 34 4
chr2 34 39 3
chr2 39 49 1
chr2 49 54 2
chr2 54 64 3
chr2 64 74 4
chr2 74 79 3
chr2 79 84 2
chr2 84 89 1
If a BED-like output is needed, --bed-format -z flags can be set, which will write a 0-based, no-header TSV output with an empty 4th column and the depth in the 5th column.
Usage:
Calculate the only the depth at each base
USAGE:
perbase only-depth [FLAGS] [OPTIONS] <reads>
FLAGS:
--bed-format
Output BED-like output format with the depth in the 5th column. Note, `-z` can be used with this to change
coordinates to 0-based to be more BED-like
-Z, --bgzip
Optionally bgzip the output
-x, --fast-mode
Calculate depth based only on read starts/stops, see docs for full details
-h, --help
Prints help information
-k, --keep-zeros
Keep positions even if they have 0 depth
-m, --mate-fix
Fix overlapping mates counts, see docs for full details
-n, --no-merge
Skip merging adjacent bases that have the same depth
-M, --skip-merging-intervals
Skip mergeing togther regions specified in the optional BED or BCF/VCF files.
**NOTE** If this is set it could result in duplicate output entries for regions that overlap. **NOTE** This
may cause issues with downstream tooling.
-V, --version
Prints version information
-z, --zero-base
Output positions as 0-based instead of 1-based
OPTIONS:
-B, --bcf-file <bcf-file>
A BCF/VCF file containing positions of interest. If specified, only bases from the given positions will be
reported on. Note that it may be more efficient to calculate depth over regions if your positions are
clustered tightly together
-b, --bed-file <bed-file>
A BED file containing regions of interest. If specified, only bases from the given regions will be reported
on
-C, --channel-size-modifier <channel-size-modifier>
The fraction of a gigabyte to allocate per thread for message passing, can be greater than 1.0 [default:
0.001]
-c, --chunksize <chunksize>
The ideal number of basepairs each worker receives. Total bp in memory at one time is (threads - 2) *
chunksize [default: 1000000]
-L, --compression-level <compression-level>
The level to use for compressing output (specified by --bgzip) [default: 2]
-T, --compression-threads <compression-threads>
The number of threads to use for compressing output (specified by --bgzip) [default: 4]
-F, --exclude-flags <exclude-flags>
SAM flags to exclude, recommended 3848 [default: 0]
-f, --include-flags <include-flags>
SAM flags to include [default: 0]
-q, --min-mapq <min-mapq>
Minimum MAPQ for a read to count toward depth [default: 0]
-o, --output <output>
Output path, defaults to stdout
-r, --ref-fasta <ref-fasta>
Indexed reference fasta, set if using CRAM
-t, --threads <threads>
The number of threads to use [default: 32]
ARGS:
<reads>
Input indexed BAM/CRAM to analyze
merge-adjacent is a utility to merge overlapping regions in a BED-like file.
It will take a file with four columns and no header as long as the columns are like:
<contig>\t<start>\t<stop>\t<depth>\n
Or it can take files with three columns with headers that are like
<REF|chrom>\t<POS|chromStart>\t<END|chromEnd>\t<DEPTH|COV>
The END|chromEnd column is optional.
perbase-merge-adjacent 0.7.5-alpha.0
Seth Stadick <[email protected]>
Merge adjacent intervals that have the same depth. Input must be sorted like: `sort -k1,1 -k2,2n in.bed > in.sorted.bed`
Generally accepts any file with no header tha is <chrom>\t<start>\t<stop>\t<depth>. The <stop> is optional. See
documentation for explaination of headers that are accepted.
USAGE:
perbase merge-adjacent [FLAGS] [OPTIONS] [in-file]
FLAGS:
-Z, --bgzip
Optionally bgzip the output
-h, --help
Prints help information
-n, --no-header
Indicate if the input file does not have a header
-V, --version
Prints version information
OPTIONS:
-T, --compression-level <compression-level>
The level to use for compressing output (specified by --bgzip) [default: 2]
-T, --compression-threads <compression-threads>
The number of threads to use for compressing output (specified by --bgzip) [default: 32]
-o, --output <output>
The output location, defaults to STDOUT
ARGS:
<in-file>
Input bed-like file, defaults to STDIN
EX:
perbase only-depth indexed.bam | perbase merge-adjacent > out.tsv