DESCRIPTION
BCFtools is a set of utilities that manipulate variant calls in the Variant
Call Format (VCF) and its binary counterpart BCF. All commands work
transparently with both VCFs and BCFs, both uncompressed and BGZF-compressed.
Most commands accept VCF, bgzipped VCF and BCF with filetype detected
automatically even when streaming from a pipe. Indexed VCF and BCF
will work in all situations. Un-indexed VCF and BCF and streams will
work in most, but not all situations.
BCFtools is designed to work on a stream. It regards an input file "-" as the
standard input (stdin) and outputs to the standard output (stdout). Several
commands can thus be combined with Unix pipes.
VERSION
This manual page was last updated 2015-01-21 15:01 GMT and refers to bcftools git version 1.1-140-g9b0e7cc+.
BCF1
The BCF1 format output by versions of samtools <= 0.1.19 is not
compatible with this version of bcftools. To read BCF1 files one can use
the view command from old versions of bcftools packaged with samtools
versions <= 0.1.19 to convert to VCF, which can then be read by
this version of bcftools.
samtools-0.1.19/bcftools/bcftools view file.bcf1 | bcftools view
VARIANT CALLING
See bcftools call for variant calling from the output of the
samtools mpileup command. In versions of samtools <= 0.1.19 calling was
done with bcftools view. Users are now required to choose between the old
samtools calling model (-c/--consensus-caller) and the new multiallelic
calling model (-m/--multiallelic-caller). The multiallelic calling model
is recommended for most tasks.
COMMANDS AND OPTIONS
Common Options
The following options are common to many bcftools commands. See usage for
specific commands to see if they apply.
-
FILE
-
Files can be both VCF or BCF, uncompressed or BGZF-compressed. The file "-"
is interpreted as standard input. Some tools may require tabix- or
CSI-indexed files.
-
-c, --collapse snps|indels|both|all|some|none|id
Controls how to treat records with duplicate positions and defines compatible
records across multiple input files. Here by "compatible" we mean records which
should be considered as identical by the tools. For example, when performing
line intersections, the desire may be to consider as identical all sites with
matching positions (bcftools isec -c all), or only sites with matching variant
type (bcftools isec -c snps -c indels), or only sites with all alleles
identical (bcftools isec -c none).
-
none
-
only records with identical REF and ALT alleles are compatible
-
some
-
only records where some subset of ALT alleles match are compatible
-
all
-
all records are compatible, regardless of whether the ALT alleles
match or not. In the case of records with the same position, only
the first will be considered and appear on output.
-
snps
-
any SNP records are compatible, regardless of whether the ALT
alleles match or not. For duplicate positions, only the first SNP
record will be considered and appear on output.
-
indels
-
all indel records are compatible, regardless of whether the REF
and ALT alleles match or not. For duplicate positions, only the
first indel record will be considered and appear on output.
-
both
-
abbreviation of "-c indels -c snps"
-
id
-
only records with identical ID column are compatible.
Supported by bcftools merge only.
-
-f, --apply-filters LIST
-
Skip sites where FILTER column does not contain any of the strings listed
in LIST. For example, to include only sites which have no filters set,
use -f .,PASS.
-
-o, --output FILE
-
When output consists of a single stream, write it to FILE rather than
to standard output, where it is written by default.
-
-O, --output-type b|u|z|v
-
Output compressed BCF (b), uncompressed BCF (u), compressed VCF (z), uncompressed VCF (v).
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
Comma-separated list of regions, see also -R, --regions-file. Note
that -r cannot be used in combination with -R.
-
-R, --regions-file FILE
-
Regions can be specified either on command line or in a VCF, BED, or
tab-delimited file (the default). The columns of the tab-delimited file
are: CHROM, POS, and, optionally, POS_TO, where positions are 1-based
and inclusive. Uncompressed files are stored in memory, while
bgzip-compressed and tabix-indexed region files are streamed. Note that
sequence names must match exactly, "chr20" is not the same as "20".
Also note that chromosome ordering in FILE will be respected,
the VCF will be processed in the order in which chromosomes first appear
in FILE. However, within chromosomes, the VCF will always be
processed in ascending genomic coordinate order no matter what order they
appear in FILE. Note that overlapping regions in FILE can result in
duplicated out of order positions in the output.
This option requires indexed VCF/BCF files. Note that -R cannot be used
in combination with -r.
-
-s, --samples [^]LIST
-
Comma-separated list of samples to include or exclude if prefixed
with "^".
-
-S, --samples-file FILE
-
File of sample names to include or exclude if prefixed with "^".
One sample per line.
The command bcftools call accepts an optional second
column indicating ploidy (0, 1 or 2) and can parse also PED files.
With bcftools call -C trio, PED file is expected.
-
-t, --targets [^]chr|chr:pos|chr:from-to|chr:from-[,…]
-
Similar as -r, --regions, but the next position is accessed by streaming the
whole VCF/BCF rather than using the tbi/csi index. Both -r and -t options
can be applied simultaneously: -r uses the index to jump to a region
and -t discards positions which are not in the targets. Unlike -r, targets
can be prefixed with "^" to request logical complement. For example, "^X,Y,MT"
indicates that sequences X, Y and MT should be skipped.
Yet another difference between the two is that -r checks both start and
end positions of indels, whereas -t checks start positions only. Note
that -t cannot be used in combination with -T.
-
-T, --targets-file [^]FILE
-
Same -t, --targets, but reads regions from a file. Note that -T
cannot be used in combination with -t.
-
-
With the call -C alleles command, third column of the targets file must
be comma-separated list of alleles, starting with the reference allele.
Such a file can be easily created from a VCF using:
bcftools query -f'%CHROM\t%POS\t%REF,%ALT\n' file.vcf
bcftools annotate [OPTIONS] FILE
This command allows to add or remove annotations.
-
-a, --annotations file
-
Bgzip-compressed and tabix-indexed file with annotations. The file
can be VCF, BED, or a tab-delimited file with mandatory columns CHROM, POS
(or, alternatively, FROM and TO), optional columns REF and ALT, and arbitrary
number of annotation columns. BED files are expected to have
the ".bed" or ".bed.gz" suffix (case-insensitive), otherwise a tab-delimited file is assumed.
Note that in case of tab-delimited file, the coordinates POS, FROM and TO are
one-based and inclusive. When REF and ALT are present, only matching VCF
records will be annotated.
When multiple ALT alleles are present in the annotation file (given as
comma-separated list of alleles), at least one must match one of the
alleles in the corresponding VCF record. Similarly, at least one
alternate allele from a multi-allelic VCF record must be present in the
annotation file.
Note that flag types, such as "INFO/FLAG", can be annotated by including
a field with the value "1" to set the flag, "0" to remove it, or "." to
keep existing flags.
See also -c, --columns and -h, --header-lines.
# Sample annotation file with columns CHROM, POS, STRING_TAG, NUMERIC_TAG
1 752566 SomeString 5
1 798959 SomeOtherString 6
# etc.
-
-c, --columns list
-
Comma-separated list of columns or tags to carry over from the annotation file
(see also -a, --annotations). If the annotation file is not a VCF/BCF,
list describes the columns of the annotation file and must include CHROM,
POS (or, alternatively, FROM and TO), and optionally REF and ALT. Unused
columns which should be ignored can be indicated by "-".
If the annotation file is a VCF/BCF, only the edited columns/tags must be present and their
order does not matter. The columns ID, QUAL, FILTER, INFO and FORMAT
can be edited, where INFO tags can be written both as "INFO/TAG" or simply "TAG",
and FORMAT tags can be written as "FORMAT/TAG" or "FMT/TAG".
To carry over all INFO annotations, use "INFO". To add all INFO annotations except
"TAG", use "^INFO/TAG". By default, existing values are replaced. To add
values without overwriting existing annotations, use "+TAG" instead of "TAG".
To replace only existing values without modifying missing annotations, use "-TAG".
If the annotation file is not a VCF/BCF, all new annotations must be
defined via -h, --header-lines.
-
-e, --exclude EXPRESSION
-
exclude sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-h, --header-lines file
-
Lines to append to the VCF header, see also -c, --columns and -a, --annotations. For example:
##INFO=<ID=NUMERIC_TAG,Number=1,Type=Integer,Description="Example header line">
##INFO=<ID=STRING_TAG,Number=1,Type=String,Description="Yet another header line">
-
-I, --set-id [+]FORMAT
-
assign ID on the fly. The format is the same as in the query
command (see below). By default all existing IDs are replaced. If the
format string is preceded by "+", only missing IDs will be set. For example,
one can use
bcftools annotate --set-id +'%CHROM\_%POS\_%REF\_%FIRST_ALT' file.vcf
-
-i, --include EXPRESSION
-
include only sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-o, --output FILE
-
see Common Options
-
-O, --output-type b|u|z|v
-
see Common Options
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
--rename-chrs file
-
rename chromosomes according to the map in file, with
"old_name new_name\n" pairs separated by whitespaces, each on a separate
line.
-
-s, --samples [^]LIST
-
subset of samples to annotate, see also Common Options
-
-S, --samples-file FILE
-
subset of samples to annotate. If the samples are named differently in the
target VCF and the -a, --annotations VCF, the name mapping can be
given as "src_name dst_name\n", separated by whitespaces, each pair on a
separate line.
-
-x, --remove list
-
List of annotations to remove. Use "FILTER" to remove all filters or
"FILTER/SomeFilter" to remove a specific filter. Similarly, "INFO" can
be used to remove all INFO tags and "FORMAT" to remove all FORMAT tags
except GT. To remove all INFO tags except "FOO" and "BAR", use
"^INFO/FOO,INFO/BAR" (and similarly for FORMAT and FILTER).
"INFO" can be abbreviated to "INF" and "FORMAT" to "FMT".
Examples:
# Remove three fields
bcftools annotate -x ID,INFO/DP,FORMAT/DP file.vcf.gz
# Remove all INFO fields and all FORMAT fields except for GT and PL
bcftools annotate -x INFO,^FORMAT/GT,FORMAT/PL file.vcf
# Add ID, QUAL and INFO/TAG, not replacing TAG if already present
bcftools annotate -a src.bcf -c ID,QUAL,+TAG dst.bcf
# Carry over all INFO and FORMAT annotations except FORMAT/GT
bcftools annotate -a src.bcf -c INFO,^FORMAT/GT dst.bcf
# Annotate from a tab-delimited file with six columns (the fifth is ignored),
# first indexing with tabix. The coordinates are 1-based.
tabix -s1 -b2 -e2 annots.tab.gz
bcftools annotate -a annots.tab.gz -h annots.hdr -c CHROM,POS,REF,ALT,-,TAG file.vcf
# Annotate from a tab-delimited file with regions (1-based coordinates, inclusive)
tabix -s1 -b2 -e3 annots.tab.gz
bcftools annotate -a annots.tab.gz -h annots.hdr -c CHROM,FROM,TO,TAG inut.vcf
# Annotate from a bed file (0-based coordinates, half-closed, half-open intervals)
bcftools annotate -a annots.bed.gz -h annots.hdr -c CHROM,FROM,TO,TAG input.vcf
bcftools call [OPTIONS] FILE
This command replaces the former bcftools view caller. Some of the original
functionality has been temporarily lost in the process of transition under
htslib, but will be added back on popular
demand. The original calling model can be invoked with the -c option.
Input/output options:
-
-A, --keep-alts
-
output all alternate alleles present in the alignments even if they do not
appear in any of the genotypes
-
-f, --format-fields list
-
comma-separated list of FORMAT fields to output for each sample. Currently
GQ and GP fields are supported. For convenience, the fields can be given
as lower case letters.
-
-g, --gvcf INT
-
output also gVCF blocks of homozygous REF calls. The parameter INT is the
minimum per-sample depth required to include a site in the non-variant
block.
-
-M, --keep-masked-ref
-
output sites where REF allele is N
-
-o, --output FILE
-
see Common Options
-
-V, --skip-variants snps|indels
-
skip indel/SNP sites
-
-v, --variants-only
-
output variant sites only
Consensus/variant calling options:
-
-c, --consensus-caller
-
the original samtools/bcftools calling method (conflicts with -m)
-
-C, --constrain alleles|trio
-
alleles
-
call genotypes given alleles. See also -T, --targets-file.
-
trio
-
call genotypes given the father-mother-child constraint. See also
-s, --samples and -n, --novel-rate.
-
-m, --multiallelic-caller
-
alternative modelfor multiallelic and rare-variant calling designed to
overcome known limitations in -c calling model (conflicts with -c)
-
-n, --novel-rate float[,…]
-
likelihood of novel mutation for constrained -C trio calling. The trio
genotype calling maximizes likelihood of a particular combination of
genotypes for father, mother and the child
P(F=i,M=j,C=k) = P(unconstrained) * Pn + P(constrained) * (1-Pn).
By providing three values, the mutation rate Pn is set explictly for SNPs,
deletions and insertions, respectively. If two values are given, the first
is interpreted as the mutation rate of SNPs and the second is used to
calculate the mutation rate of indels according to their length as
Pn=float*exp(-a-b*len), where a=22.8689, b=0.2994 for insertions and
a=21.9313, b=0.2856 for deletions [pubmed:23975140]. If only one value is
given, the same mutation rate Pn is used for SNPs and indels.
-
-p, --pval-threshold float
-
with -c, accept variant if P(ref|D) < float.
-
-P, --prior float
-
expected substitution rate, or 0 to disable the prior.
-
-t, --targets file|chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-X, --chromosome-X
-
haploid output for male samples (requires PED file with -s)
-
-Y, --chromosome-Y
-
haploid output for males and skips females (requires PED file with -s)
bcftools concat [OPTIONS] FILE1 FILE2 […]
Concatenate or combine VCF/BCF files. All source files must have the same sample
columns appearing in the same order. Can be used, for example, to
concatenate chromosome VCFs into one VCF, or combine a SNP VCF and an indel
VCF into one. The input files must be sorted by chr and position. The files
must be given in the correct order to produce sorted VCF on output unless
the -a, --allow-overlaps option is specified.
-
-a, --allow-overlaps
-
First coordinate of the next file can precede last record of the current file.
-
-D, --remove-duplicates
-
If a record is present in multiple files, output only the first instance.
Requires -a, --allow-overlaps.
-
-f, --file-list FILE
-
Read the list of files from a file.
-
-l, --ligate
-
Ligate phased VCFs by matching phase at overlapping haplotypes
-
-o, --output FILE
-
see Common Options
-
-O, --output-type b|u|z|v
-
see Common Options
-
-q, --min-PQ INT
-
Break phase set if phasing quality is lower than INT
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options. Requires -a, --allow-overlaps.
-
-R, --regions-file FILE
-
see Common Options. Requires -a, --allow-overlaps.
bcftools consensus [OPTIONS] FILE
Create consensus sequence by applying VCF variants to a reference fasta file.
-
-f, --fasta-ref FILE
-
reference sequence in fasta format
-
-H, --haplotype 1|2
-
apply variants for the given haplotype. This option requires -s, unless
exactly one sample is present in the VCF
-
-i, --iupac-codes
-
output variants in the form of IUPAC ambiguity codes
-
-m, --mask FILE
-
BED file or TAB file with regions to be replaced with N. See discussion
of --regions-file in Common Options for file
format details.
-
-o, --output FILE
-
write output to a file
-
-s, --sample NAME
-
apply variants of the given sample
Examples:
# Apply variants present in sample "NA001", output IUPAC codes for hets
bcftools consensus -i -s NA001 -f in.fa in.vcf.gz > out.fa
# Create consensus for one region. The fasta header lines are then expected
# in the form ">chr:from-to".
samtools faidx ref.fa 8:11870-11890 | bcftools consensus in.vcf.gz -o out.fa
bcftools convert [OPTIONS] FILE
GEN/SAMPLE conversion:
-
-G, --gensample2vcf prefix or gen-file,sample-file
-
convert IMPUTE2 output to VCF. The second column must be of the form
"CHROM:POS_REF_ALT" to detect possible strand swaps; IMPUTE2 leaves the
first one empty ("--") when sites from reference panel are filled in. See
also -g below.
-
-g, --gensample prefix or gen-file,sample-file
-
convert from VCF to gen/sample format used by IMPUTE2 and SHAPEIT.
The columns of .gen file format are ID1,ID2,POS,A,B followed by three
genotype probabilities P(AA), P(AB), P(BB) for each sample. In order to
prevent strand swaps, the program uses IDs of the form "CHROM:POS_REF_ALT".
For example:
.gen
----
1:111485207_G_A 1:111485207_G_A 111485207 G A 0 1 0 0 1 0
1:111494194_C_T 1:111494194_C_T 111494194 C T 0 1 0 0 0 1
.sample
-------
ID_1 ID_2 missing
0 0 0
sample1 sample1 0
sample2 sample2 0
-
--tag STRING
-
tag to take values for .gen file: GT,PL,GL,GP
gVCF conversion:
-
--gvcf2vcf
-
convert gVCF to VCF, expanding REF blocks into sites. Only sites
with FILTER set to "PASS" or "." will be expanded.
HAPS/SAMPLE conversion:
-
--hapsample2vcf prefix or haps-file,sample-file
-
convert from haps/sample format to VCF. The columns of .haps file are
similar to .gen file above, but there are only two haplotype columns per
sample. Note that the first column of the haps file is expected to be in
the form "CHR:POS_REF_ALT", for example:
.haps
----
1:111485207_G_A rsID1 111485207 G A 0 1 0 0
1:111494194_C_T rsID2 111494194 C T 0 1 0 0
HAPS/LEGEND/SAMPLE conversion:
-
-H, --haplegendsample2vcf prefix or haps-file,legend-file,sample-file
-
convert from haps/legend/sample format used by IMPUTE2 to VCF, see
also -h, --hapslegendsample below.
-
-h, --haplegendsample prefix or haps-file,legend-file,sample-file
-
convert from VCF to haps/legend/sample format used by IMPUTE2 and SHAPEIT.
The columns of .legend file ID,POS,REF,ALT. In order to prevent strand
swaps, the program uses IDs of the form "CHROM:POS_REF_ALT". The .sample
file is quite basic at the moment with columns for population, group and
sex expected to be edited by the user. For example:
.haps
-----
0 1 0 0 1 0
0 1 0 0 0 1
.legend
-------
id position a0 a1
1:111485207_G_A 111485207 G A
1:111494194_C_T 111494194 C T
.sample
-------
sample population group sex
sample1 sample1 sample1 2
sample2 sample2 sample2 2
-
--haploid2diploid
-
with -h option converts haploid genotypes to homozygous diploid
genotypes. For example, the program will print 0 0 instead of the
default 0 -. This is useful for programs which do not handle haploid
genotypes correctly.
-
--vcf-ids
-
output VCF IDs instead of "CHROM:POS_REF_ALT" IDs
TSV conversion:
-
--tsv2vcf file
-
convert from TSV (tab-separated values) format (such as generated by
23andMe) to VCF. The input file fields can be tab- or space- delimited
-
-c, --columns list
-
comma-separated list of fields in the input file. In the current
version, the fields CHROM, POS, ID, and AA are expected and
can appear in arbitrary order, columns which should be ignored in the input
file can be indicated by "-".
The AA field lists alleles on the forward reference strand,
for example "CC" or "CT" for diploid genotypes or "C"
for haploid genotypes (sex chromosomes). Insertions and deletions
are not supported yet, missing data can be indicated with "--".
-
-f, --fasta-ref file
-
reference sequence in fasta format
-
-s, --samples LIST
-
list of sample names. See Common Options
-
-S, --samples-file FILE
-
file of sample names. See Common Options
Example:
# Convert 23andme results into VCF
bcftools convert -c ID,CHROM,POS,AA -s SampleName -f 23andme-ref.fa --tsv2vcf 23andme.txt -Oz -o out.vcf.gz
bcftools filter [OPTIONS] FILE
Apply fixed-threshold filters.
-
-e, --exclude EXPRESSION
-
exclude sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-g, --SnpGap INT
-
filter SNPs within INT base pairs of an indel. The following example
demonstrates the logic of --SnpGap 3 applied on a deletion and
an insertion:
The SNPs at positions 1 and 7 are filtered, positions 0 and 8 are not:
0123456789
ref .G.GT..G..
del .A.G-..A..
Here the positions 1 and 6 are filtered, 0 and 7 are not:
0123-456789
ref .G.G-..G..
ins .A.GT..A..
-
-G, --IndelGap INT
-
filter clusters of indels separated by INT or fewer base pairs allowing
only one to pass. The following example demonstrates the logic of
--IndelGap 2 applied on a deletion and an insertion:
The second indel is filtered:
012345678901
ref .GT.GT..GT..
del .G-.G-..G-..
And similarly here, the second is filtered:
01 23 456 78
ref .A-.A-..A-..
ins .AT.AT..AT..
-
-i, --include EXPRESSION
-
include only sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-m, --mode [+x]
-
define behaviour at sites with existing FILTER annotations. The default
mode replaces existing filters of failed sites with a new FILTER string
while leaving sites which pass untouched when non-empty and setting to
"PASS" when the FILTER string is absent. The "+" mode appends new FILTER
strings of failed sites instead of replacing them. The "x" mode resets
filters of sites which pass to "PASS". Modes "+" and "x" can both be set.
-
-o, --output FILE
-
see Common Options
-
-O, --output-type b|u|z|v
-
see Common Options
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
-s, --soft-filter STRING|+
-
annotate FILTER column with STRING or, with +, a unique filter name generated
by the program ("Filter%d").
-
-S, --set-GTs .|0
-
set genotypes of failed samples to missing value (.) or reference allele (0)
-
-t, --targets chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-T, --targets-file file
-
see Common Options
bcftools gtcheck [OPTIONS] [-g genotypes.vcf.gz] query.vcf.gz
Checks sample identity or, without -g, multi-sample cross-check is performed.
-
-a, --all-sites
-
output for all sites
-
-g, --genotypes genotypes.vcf.gz
-
reference genotypes to compare against
-
-G, --GTs-only INT
-
use genotypes (GT) instead of genotype likelihoods (PL). When set to 1,
reported discordance is the number of non-matching GTs, otherwise the
number INT is interpreted as phred-scaled likelihood of unobserved
genotypes.
-
-H, --homs-only
-
consider only genotypes which are homozygous in both genotypes and
query VCF. This may be useful with low coverage data.
-
-p, --plot PREFIX
-
produce plots
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
-s, --query-sample STRING
-
query sample in query.vcf.gz. By default, the first sample is checked.
-
-S, --target-sample STRING
-
target sample in the -g file, used only for plotting, not for analysis
-
-t, --targets file
-
see Common Options
-
-T, --targets-file file
-
see Common Options
Output files format:
-
CN, Discordance
-
Pairwise discordance for all sample pairs is calculated as
\sum_s { min_G { PL_a(G) + PL_b(G) } },
-
-
where the sum runs over all sites s and G is the the most likely
genotype shared by both samples a and b. When PL field is not
present, a constant value 99 is used for the unseen genotypes. With
-G, the value 1 can be used instead; the discordance value then
gives exactly the number of differing genotypes.
-
SM, Average Discordance
-
Average discordance between sample a and all other samples.
-
SM, Average Depth
-
Average depth at evaluated sites, or 1 if FORMAT/DP field is not
present.
-
SM, Average Number of sites
-
The average number of sites used to calculate the discordance. In
other words, the average number of non-missing PLs/genotypes seen
both samples.
bcftools index [OPTIONS] <in.bcf>|<in.vcf.gz>
Creates index for bgzip compressed VCF/BCF files for random access. CSI
(coordinate-sorted index) is created by default. The CSI format
supports indexing of chromosomes up to length 2^31. TBI (tabix index)
index files, which support chromosome lengths up to 2^29, can be
created by using the -t/--tbi option or using the tabix program
packaged with htslib. When loading an index file, bcftools will try
the CSI first and then the TBI.
Indexing options:
-
-c, --csi
-
generate CSI-format index for VCF/BCF files [default]
-
-f, --force
-
overwrite index if it already exists
-
-m, --min-shift INT
-
set minimal interval size for CSI indices to 2^INT; default: 14
-
-t, --tbi
-
generate TBI-format index for VCF files
Stats options:
-
-n, --nrecords
-
print the number of records based on the CSI or TBI index files
-
-s, --stats
-
Print per contig stats based on the CSI or TBI index files.
Output format is three tab-delimited columns listing the contig
name, contig length (. if unknown) and number of records for
the contig. Contigs with zero records are not printed.
bcftools isec [OPTIONS] A.vcf.gz B.vcf.gz […]
Creates intersections, unions and complements of VCF files. Depending
on the options, the program can output records from one (or more) files
which have (or do not have) corresponding records with the same position
in the other files.
-
-c, --collapse snps|indels|both|all|some|none
-
see Common Options
-
-C, --complement
-
output positions present only in the first file but missing in the others
-
-e, --exclude -|EXPRESSION
-
exclude sites for which EXPRESSION is true. If -e (or -i)
appears only once, the same filtering expression will be applied to all
input files. Otherwise, -e or -i must be given for each input file.
To indicate that no filtering should be performed on a file, use "-" in
place of EXPRESSION, as shown in the example below.
For valid expressions see EXPRESSIONS.
-
-f, --apply-filters LIST
-
see Common Options
-
-i, --include EXPRESSION
-
include only sites for which EXPRESSION is true. See discussion
of -e, --exclude above.
-
-n, --nfiles [+-=]INT
-
output positions present in this many (=), this many or more (+), or this
many or fewer (-) files
-
-o, --output FILE
-
see Common Options. When several files are being
output, their names are controlled via -p instead.
-
-O, --output-type b|u|z|v
-
see Common Options
-
-p, --prefix DIR
-
if given, subset each of the input files accordingly. See also -w.
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
-t, --targets chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-T, --targets-file file
-
see Common Options
-
-w, --write LIST
-
list of input files to output given as 1-based indices. With -p and no
-w, all files are written.
Examples:
Create intersection and complements of two sets saving the output in dir/*
bcftools isec -p dir A.vcf.gz B.vcf.gz
Filter sites in A and B (but not in C) and create intersection
bcftools isec -e'MAF<0.01' -i'dbSNP=1' -e- A.vcf.gz B.vcf.gz C.vcf.gz -p dir
Extract and write records from A shared by both A and B using exact allele match
bcftools isec -p dir -n=2 -w1 A.vcf.gz B.vcf.gz
Extract records private to A or B comparing by position only
bcftools isec -p dir -n-1 -c all A.vcf.gz B.vcf.gz
bcftools merge [OPTIONS] A.vcf.gz B.vcf.gz […]
Merge multiple VCF/BCF files from non-overlapping sample sets to create one
multi-sample file. For example, when merging file A.vcf.gz containing
samples S1, S2 and S3 and file B.vcf.gz containing samples S3 and
S4, the output file will contain four samples named S1, S2, S3, 2:S3
and S4.
Note that it is responsibility of the user to ensure that the sample names are
unique across all files. If they are not, the program will exit with an error
unless the option --force-samples is given. The sample names can be
also given explicitly using the --print-header and --use-header options.
Note that only records from different files can be merged, never from the same file.
For "vertical" merge take a look at bcftools norm instead.
-
--force-samples
-
if the merged files contain duplicate samples names, proceed anyway.
Duplicate sample names will be resolved by prepending index of the file
as it appeared on the command line to the conflicting sample name (see
2:S3 in the above example).
-
--print-header
-
print only merged header and exit
-
--use-header FILE
-
use the VCF header in the provided text FILE
-
-f, --apply-filters LIST
-
see Common Options
-
-i, --info-rules -|TAG:METHOD[,…]
-
Rules for merging INFO fields (scalars or vectors) or - to disable the
default rules. METHOD is one of sum, avg, min, max, join.
-
-l, --file-list FILE
-
read file names from FILE
-
-m, --merge snps|indels|both|all|none|id
-
The option controls what types of multiallelic records can be created:
-m none .. no new multiallelics, output multiple records instead
-m snps .. allow multiallelic SNP records
-m indels .. allow multiallelic indel records
-m both .. both SNP and indel records can be multiallelic
-m all .. SNP records can be merged with indel records
-m id .. merge by ID
bcftools norm [OPTIONS] file.vcf.gz
Left-align and normalize indels, check if REF alleles match the reference,
split multiallelic sites into multiple rows; recover multiallelics from
multiple rows.
-
-D, --remove-duplicates
-
remove duplicate lines of the same type
-
-f, --fasta-ref FILE
-
reference sequence
-
-m, --multiallelics ←|+>[snps|indels|both|any]
-
split multiallelic sites into biallelic records (-) or join
biallelic sites into multiallelic records (+). An optional type string
can follow which controls variant types which should be split or merged
together: If only SNP records should be split or merged, specify snps; if
both SNPs and indels should be merged separately into two records, specify
both; if SNPs and indels should be merged into a single record, specify
any.
-
-o, --output FILE
-
see Common Options
-
-O, --output-type b|u|z|v
-
see Common Options
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
-s, --strict-filter
-
when merging (-m+), merged site is PASS only if all sites being merged PASS
-
-t, --targets LIST
-
see Common Options
-
-T, --targets-file FILE
-
see Common Options
-
-w, --site-win INT
-
maximum distance between two records to consider when locally
sorting variants which changed position during the realignment
bcftools plugin NAME [OPTIONS] FILE — [PLUGIN OPTIONS]
VCF input options:
-
-e, --exclude EXPRESSION
-
exclude sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-i, --include EXPRESSION
-
include only sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
-t, --targets chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-T, --targets-file file
-
see Common Options
Plugin options:
-
-h, --help
-
list plugin’s options
-
-l, --list-plugins
-
List all available plugins. If not installed systemwide, set the environment
variable LD_LIBRARY_PATH (linux) or DYLD_LIBRARY_PATH (Mac OS X) to include
directory where libhts.so is located. The BCFTOOLS_PLUGINS
environment variable tells the program which directories to search.
-
-v, --verbose
-
print debugging information to debug plugin failure
List of plugins coming with the distribution:
-
counts
-
a minimal plugin which counts number of SNPs, Indels, and total number of sites.
-
dosage
-
print genotype dosage. By default the plugin searches for PL, GL and GT, in
that order.
-
fill-AN-AC
-
fill INFO fields AN and AC.
-
fix-ploidy
-
sets correct ploidy
-
frameshifts
-
annotate frameshift indels
-
missing2ref
-
sets missing genotypes ("./.") to ref allele ("0/0" or "0|0")
-
tag2tag
-
Convert between similar tags, such as GL and GP.
-
vcf2sex
-
determine sample sex by checking genotypes in haploid regions
Examples:
# List options common to all plugins
bcftools plugin
# List available plugins
bcftools plugin -l
# One can run plugins in several ways
bcftools plugin counts in.vcf
bcftools +counts in.vcf
cat in.vcf | bcftools +counts
# Print usage information of plugin "dosage"
bcftools +dosage -h
# Replace missing genotypes with 0/0
bcftools +missing2ref in.vcf
# Replace missing genotypes with 0|0
bcftools +missing2ref in.vcf -- -p
Plugins troubleshooting:
Things to check if your plugin does not show up in the bcftools plugin -l output:
Plugins API:
// Short description used by 'bcftools plugin -l'
const char *about(void);
// Longer description used by 'bcftools +name -h'
const char *usage(void);
// Called once at startup, allows to initialize local variables.
// Return 1 to suppress normal VCF/BCF header output, -1 on critical
// errors, 0 otherwise.
int init(int argc, char **argv, bcf_hdr_t *in_hdr, bcf_hdr_t *out_hdr);
// Called for each VCF record, return NULL to suppress the output
bcf1_t *process(bcf1_t *rec);
// Called after all lines have been processed to clean up
void destroy(void);
bcftools query [OPTIONS] file.vcf.gz [file.vcf.gz […]]
Extracts fields from VCF or BCF files and outputs them in user-defined format.
-
-c, --collapse snps|indels|both|all|some|none
-
see Common Options
-
-e, --exclude EXPRESSION
-
exclude sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-f, --format FORMAT
-
learn by example, see below
-
-H, --print-header
-
print header
-
-i, --include EXPRESSION
-
include only sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-l, --list-samples
-
list sample names and exit
-
-o, --output FILE
-
see Common Options
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
-s, --samples LIST
-
see Common Options
-
-S, --samples-file FILE
-
see Common Options
-
-t, --targets chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-T, --targets-file file
-
see Common Options
-
-v, --vcf-list FILE
-
process multiple VCFs listed in the file
Format:
%CHROM The CHROM column (similarly also other columns: POS, ID, REF, ALT, QUAL, FILTER)
%INFO/TAG Any tag in the INFO column
%TYPE Variant type (REF, SNP, MNP, INDEL, OTHER)
%MASK Indicates presence of the site in other files (with multiple files)
%TAG{INT} Curly brackets to subscript vectors (0-based)
%FIRST_ALT Alias for %ALT{0}
[] The brackets loop over all samples
%GT Genotype (e.g. 0/1)
%TGT Translated genotype (e.g. C/A)
%IUPACGT Genotype translated to IUPAC ambiguity codes (e.g. M instead of C/A)
%LINE Prints the whole line
%SAMPLE Sample name
Examples:
bcftools query -f '%CHROM %POS %REF %ALT{0}\n' file.vcf.gz
bcftools query -f '%CHROM\t%POS\t%REF\t%ALT[\t%SAMPLE=%GT]\n' file.vcf.gz
bcftools reheader [OPTIONS] file.vcf.gz
Modify header of VCF/BCF files, change sample names.
-
-h, --header FILE
-
new VCF header
-
-o, --output FILE
-
see Common Options
-
-s, --samples FILE
-
new sample names, one name per line, in the same order as they appear
in the VCF file. Alternatively, only samples which need to be renamed
can be listed as "old_name new_name\n" pairs separated by
whitespaces, each on separate line.
bcftools roh [OPTIONS] file.vcf.gz
A program for detecting runs of homo/autozygosity. Only bi-allelic sites
are considered.
The HMM model:
Notation:
D = Data, AZ = autozygosity, HW = Hardy-Weinberg (non-autozygosity),
f = non-ref allele frequency
Emission probabilities:
oAZ = P_i(D|AZ) = (1-f)*P(D|RR) + f*P(D|AA)
oHW = P_i(D|HW) = (1-f)^2 * P(D|RR) + f^2 * P(D|AA) + 2*f*(1-f)*P(D|RA)
Transition probabilities:
tAZ = P(AZ|HW) .. from HW to AZ, the -a parameter
tHW = P(HW|AZ) .. from AZ to HW, the -H parameter
P(AZ|AZ) = 1 - P(HW|AZ) = 1 - tHW
P(HW|HW) = 1 - P(AZ|HW) = 1 - tAZ
ci = P_i(C) .. probability of cross-over at site i, from genetic map
AZi = P_i(AZ) .. probability of site i being AZ/non-AZ, scaled so that AZi+HWi = 1
HWi = P_i(HW)
P_{i+1}(AZ) = oAZ * max[(1-tHW) * (1-ci) * AZ{i-1} , tAZ * ci * (1-AZ{i-1})]
P_{i+1}(HW) = oHW * max[(1-tAZ) * (1-ci) * (1-AZ{i-1}) , tHW * ci * AZ{i-1}]
General Options:
-
--AF-tag TAG
-
use the specified INFO tag TAG as an allele frequency estimate
instead of the defaul AC and AN tags. Sites which do not have TAG
will be skipped.
-
--AF-file FILE
-
Read allele frequencies from a tab-delimited file containing
the columns: CHROM\tPOS\tREF,ALT\tAF. The file can be compressed with
bgzip and indexed with tabix -s1 -b2 -e2. Sites which are not present in
the FILE or have different reference or alternate allele will be skipped.
Note that such a file can be easily created from a VCF using:
bcftools query -f'%CHROM\t%POS\t%REF,%ALT\t%INFO/TAG\n' file.vcf | bgzip -c > freqs.tab.gz
-
-e, --estimate-AF FILE
-
recalculate INFO/AC and INFO/AN on the fly, using either all samples
("-") or samples listed in FILE. By default, allele frequency is
estimated from AC and AN counts which are already present in the INFO
field.
-
-G, --GTs-only FLOAT
-
use genotypes (FORMAT/GT fields) ignoring genotype likelihoods (FORMAT/PL),
setting PL of unseen genotypes to FLOAT. Safe value to use is 30 to
account for GT errors.
-
-I, --skip-indels
-
skip indels as their genotypes are usually enriched for errors
-
-m, --genetic-map FILE
-
genetic map in the format required also by IMPUTE2. Only the first and
third column are used (position and Genetic_Map(cM)). The FILE can
chromosome name.
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
-s, --sample name
-
the name of sample to analyze
-
-t, --targets chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-T, --targets-file file
-
see Common Options
HMM Options:
-
-a, --hw-to-az FLOAT
-
P(AZ|HW) transition probability from AZ (autozygous) to HW (Hardy-Weinberg) state
-
-H, --az-to-hw FLOAT
-
P(HW|AZ) transition probability from HW to AZ state
-
-V, --viterbi-training
-
perform Viterbi training to estimate transition probabilities
bcftools stats [OPTIONS] A.vcf.gz [B.vcf.gz]
Parses VCF or BCF and produces text file stats which is suitable for machine
processing and can be plotted using plot-vcfstats. When two files are given,
the program generates separate stats for intersection and the complements. By
default only sites are compared, -s/-S must given to include also sample
columns.
-
-1, --1st-allele-only
-
consider only 1st allele at multiallelic sites
-
-c, --collapse snps|indels|both|all|some|none
-
see Common Options
-
-d, --depth INT,INT,INT
-
ranges of depth distribution: min, max, and size of the bin
-
--debug
-
produce verbose per-site and per-sample output
-
-e, --exons file.gz
-
tab-delimited file with exons for indel frameshifts statistics. The columns
of the file are CHR, FROM, TO, with 1-based, inclusive, positions. The file
is BGZF-compressed and indexed with tabix
tabix -s1 -b2 -e3 file.gz
-
-f, --apply-filters LIST
-
see Common Options
-
-F, --fasta-ref ref.fa
-
faidx indexed reference sequence file to determine INDEL context
-
-i, --split-by-ID
-
collect stats separately for sites which have the ID column set ("known
sites") or which do not have the ID column set ("novel sites").
-
-r, --regions chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-R, --regions-file file
-
see Common Options
-
-s, --samples LIST
-
see Common Options
-
-S, --samples-file FILE
-
see Common Options
-
-t, --targets chr|chr:pos|chr:from-to|chr:from-[,…]
-
see Common Options
-
-T, --targets-file file
-
see Common Options
bcftools view [OPTIONS] file.vcf.gz [REGION […]]
View, subset and filter VCF or BCF files by position and filtering expression.
Convert between VCF and BCF. Former bcftools subset.
Output options
-
-G, --drop-genotypes
-
drop individual genotype information (after subsetting if -s option is set)
-
-h, --header-only
-
output the VCF header only
-
-H, --no-header
-
suppress the header in VCF output
-
-l, --compression-level [0-9]
-
compression level. 0 stands for uncompressed, 1 for best speed and 9 for
best compression.
-
-O, --output-type b|u|z|v
-
see Common Options
-o, --output-file FILE:
output file name. If not present, the default is to print to standard output (stdout).
Subset options:
-
-a, --trim-alt-alleles
-
trim alternate alleles not seen in subset. Type A, G and R INFO and FORMAT fields will also be trimmed
-
-I, --no-update
-
do not (re)calculate INFO fields for the subset (currently INFO/AC and INFO/AN)
-
-s, --samples LIST
-
see Common Options
-
-S, --samples-file FILE
-
see Common Options
Filter options:
-
-c, --min-ac INT[:nref|:alt1|:minor|:major|:'nonmajor']
-
minimum allele count (INFO/AC) of sites to be printed.
Specifying the type of allele is optional and can be set to
non-reference (nref, the default), 1st alternate (alt1), the least
frequent (minor), the most frequent (major) or sum of all but the
most frequent (nonmajor) alleles.
-
-C, --max-ac INT[:nref|:alt1|:minor|:'major'|:'nonmajor']
-
maximum allele count (INFO/AC) of sites to be printed.
Specifying the type of allele is optional and can be set to
non-reference (nref, the default), 1st alternate (alt1), the least
frequent (minor), the most frequent (major) or sum of all but the
most frequent (nonmajor) alleles.
-
-e, --exclude EXPRESSION
-
exclude sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-f, --apply-filters LIST
-
see Common Options
-
-g, --genotype [^][hom|het|miss]
-
include only sites with one or more homozygous (hom), heterozygous
(het) or missing (miss) genotypes. When prefixed with ^, the logic
is reversed; thus ^het excludes sites with heterozygous genotypes.
-
-i, --include EXPRESSION
-
include sites for which EXPRESSION is true. For valid expressions see
EXPRESSIONS.
-
-k, --known
-
print known sites only (ID column is not ".")
-
-m, --min-alleles INT
-
print sites with at least INT alleles listed in REF and ALT columns
-
-M, --max-alleles INT
-
print sites with at most INT alleles listed in REF and ALT columns. Use -m2 -M2 -v snps to only view biallelic SNPs.
-
-n, --novel
-
print novel sites only (ID column is ".")
-
-p, --phased
-
print sites where all samples are phased. Haploid genotypes are
considered phased. Missing genotypes considered unphased unless the
phased bit is set.
-
-P, --exclude-phased
-
exclude sites where all samples are phased
-
-q, --min-af FLOAT[:nref|:alt1|:minor|:'major'|:'nonmajor']
-
minimum allele frequency (INFO/AC / INFO/AN) of sites to be printed.
Specifying the type of allele is optional and can be set to
non-reference (nref, the default), 1st alternate (alt1), the least
frequent (minor), the most frequent (major) or sum of all but the
most frequent (nonmajor) alleles.
-
-Q, --max-af FLOAT[:nref|:alt1|:minor|:'major'|:'nonmajor']
-
maximum allele frequency (INFO/AC / INFO/AN) of sites to be printed.
Specifying the type of allele is optional and can be set to
non-reference (nref, the default), 1st alternate (alt1), the least
frequent (minor), the most frequent (major) or sum of all but the
most frequent (nonmajor) alleles.
-
-u, --uncalled
-
print sites without a called genotype
-
-U, --exclude-uncalled
-
exclude sites without a called genotype
-
-v, --types snps|indels|mnps|other
-
comma-separated list of variant types to select
-
-V, --exclude-types snps|indels|mnps|other
-
comma-separated list of variant types to exclude
-
-x, --private
-
print sites where only the subset samples carry an non-reference allele
-
-X, --exclude-private
-
exclude sites where only the subset samples carry an non-reference allele
EXPRESSIONS
These filtering expressions are accepted by annotate,
filter, query and view commands.
Valid expressions may contain:
numerical constants, string constants, file names
1, 1.0, 1e-4
"String"
@file_name
arithmetic operators
+,*,-,/
comparison operators
== (same as =), >, >=, <=, <, !=
regex operators "~" and its negation "!~"
INFO/HAYSTACK ~ "needle"
parentheses
(, )
logical operators
&& (same as &), ||, |
INFO tags, FORMAT tags, column names
INFO/DP or DP
FORMAT/DV, FMT/DV, or DV
FILTER, QUAL, ID, REF, ALT[0]
1 (or 0) to test the presence (or absence) of a flag
FlagA=1 && FlagB=0
TYPE for variant type in REF,ALT columns (indel,snp,mnp,ref,other)
TYPE="indel" | TYPE="snp"
array subscripts, "*" for any field
(DP4[0]+DP4[1])/(DP4[2]+DP4[3]) > 0.3
DP4[*] == 0
CSQ[*] ~ "missense_variant.*deleterious"
function on FORMAT tags (over samples) and INFO tags (over vector fields)
MAX, MIN, AVG, SUM, STRLEN, ABS
variables calculated on the fly if not present: number of alternate alleles;
number of samples; count of alternate alleles; minor allele count (similar to
AC but is always smaller than 0.5); frequency of alternate alleles (AF=AC/AN);
frequency of minor alleles (MAF=MAC/AN); number of alleles in called genotypes
N_ALT, N_SAMPLES, AC, MAC, AF, MAF, AN
Notes:
-
String comparisons and regular expressions are case-insensitive
-
If the subscript "*" is used in regular expression search, the
whole field is treated as one string. For example, the regex STR[*]~"B,C" will be
true for the string vector INFO/STR=AB,CD.
-
Variables and function names are case-insensitive, but not tag names. For example,
"qual" can be used instead of "QUAL", "strlen()" instead of "STRLEN()" , but
not "dp" instead of "DP".
Examples:
MIN(DV)>5
MIN(DV/DP)>0.3
MIN(DP)>10 & MIN(DV)>3
QUAL>10 | FMT/GQ>10 .. selects only GQ>10 samples
QUAL>10 || FMT/GQ>10 .. selects all samples at QUAL>10 sites
TYPE="snp" && QUAL>=10 && (DP4[2]+DP4[3] > 2)
MIN(DP)>35 && AVG(GQ)>50
ID=@file .. selects lines with ID present in the file
ID!=@~/file .. skip lines with ID present in the ~/file
MAF[0]<0.05 .. select rare variants at 5% cutoff
Shell expansion:
Note that expressions must often be quoted because some characters
have special meaning in the shell.
An example of expression enclosed in single quotes which cause
that the whole expression is passed to the program as intended:
bcftools view -i '%ID!="." & MAF[0]<0.01'
Please refer to the documentation of your shell for details.