Create an alternative reference by combining a fasta with a vcf.

Category Reference

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Overview

Generate an alternative reference sequence over the specified interval

Given a variant callset, this tool replaces the reference bases at variation sites with the bases supplied in the corresponding callset records. Additionally, it allows for one or more "snp-mask" VCFs to set overlapping bases to 'N'.

The output format can be partially controlled using the provided command-line arguments. Specify intervals with the usual -L argument to output only the reference bases within your intervals. Overlapping intervals are automatically merged; reference bases for each disjoint interval will be output as a separate fasta sequence (named numerically in order).

Caveats

• If there are multiple variants that start at a site, it chooses one of them randomly.
• When there are overlapping indels (but with different start positions) only the first will be chosen.
• This tool works only for SNPs and for simple indels (but not for things like complex substitutions).

Input

The reference, requested intervals, and any number of variant files.

Output

A FASTA file representing the requested intervals.

Usage example

 gatk FastaAlternateReferenceMaker \
   -R reference.fasta \
   -O output.fasta \
   -L input.intervals \
   -V input.vcf \

   [--snp-mask mask.vcf]
 

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Additional Information

Read filters

This Read Filter is automatically applied to the data by the Engine before processing by FastaAlternateReferenceMaker.

• WellformedReadFilter

FastaAlternateReferenceMaker specific arguments

This table summarizes the command-line arguments that are specific to this tool. For more details on each argument, see the list further down below the table or click on an argument name to jump directly to that entry in the list.

Argument name(s)	Default value	Summary
Required Arguments
--output  -O	null	Path to write the output fasta to
--reference  -R	null	Reference sequence file
--variant  -V	null	A source of variants to merge with the reference sequence.
Optional Tool Arguments
--arguments_file	[]	read one or more arguments files and add them to the command line
--cloud-index-prefetch-buffer  -CIPB	-1	Size of the cloud-only prefetch buffer (in MB; 0 to disable). Defaults to cloudPrefetchBuffer if unset.
--cloud-prefetch-buffer  -CPB	40	Size of the cloud-only prefetch buffer (in MB; 0 to disable).
--disable-bam-index-caching  -DBIC	false	If true, don't cache bam indexes, this will reduce memory requirements but may harm performance if many intervals are specified. Caching is automatically disabled if there are no intervals specified.
--disable-sequence-dictionary-validation	false	If specified, do not check the sequence dictionaries from our inputs for compatibility. Use at your own risk!
--gcs-max-retries  -gcs-retries	20	If the GCS bucket channel errors out, how many times it will attempt to re-initiate the connection
--gcs-project-for-requester-pays	""	Project to bill when accessing "requester pays" buckets. If unset, these buckets cannot be accessed.
--help  -h	false	display the help message
--interval-merging-rule  -imr	ALL	Interval merging rule for abutting intervals
--intervals  -L	[]	One or more genomic intervals over which to operate
--line-width	60	Maximum length of sequence to write per line
--sites-only-vcf-output	false	If true, don't emit genotype fields when writing vcf file output.
--snp-mask	null	SNP mask VCF file
--snp-mask-priority	false	Give the snp mask priority over the input VCF.
--use-iupac-sample	null	If specified, heterozygous SNP sites will be output using IUPAC ambiguity codes given the genotypes for this sample
--version	false	display the version number for this tool
Optional Common Arguments
--add-output-sam-program-record	true	If true, adds a PG tag to created SAM/BAM/CRAM files.
--add-output-vcf-command-line	true	If true, adds a command line header line to created VCF files.
--create-output-bam-index  -OBI	true	If true, create a BAM/CRAM index when writing a coordinate-sorted BAM/CRAM file.
--create-output-bam-md5  -OBM	false	If true, create a MD5 digest for any BAM/SAM/CRAM file created
--create-output-variant-index  -OVI	true	If true, create a VCF index when writing a coordinate-sorted VCF file.
--create-output-variant-md5  -OVM	false	If true, create a a MD5 digest any VCF file created.
--disable-read-filter  -DF	[]	Read filters to be disabled before analysis
--disable-tool-default-read-filters	false	Disable all tool default read filters (WARNING: many tools will not function correctly without their default read filters on)
--exclude-intervals  -XL	[]	One or more genomic intervals to exclude from processing
--gatk-config-file	null	A configuration file to use with the GATK.
--input  -I	[]	BAM/SAM/CRAM file containing reads
--interval-exclusion-padding  -ixp	0	Amount of padding (in bp) to add to each interval you are excluding.
--interval-padding  -ip	0	Amount of padding (in bp) to add to each interval you are including.
--interval-set-rule  -isr	UNION	Set merging approach to use for combining interval inputs
--lenient  -LE	false	Lenient processing of VCF files
--QUIET	false	Whether to suppress job-summary info on System.err.
--read-filter  -RF	[]	Read filters to be applied before analysis
--read-index	[]	Indices to use for the read inputs. If specified, an index must be provided for every read input and in the same order as the read inputs. If this argument is not specified, the path to the index for each input will be inferred automatically.
--read-validation-stringency  -VS	SILENT	Validation stringency for all SAM/BAM/CRAM/SRA files read by this program. The default stringency value SILENT can improve performance when processing a BAM file in which variable-length data (read, qualities, tags) do not otherwise need to be decoded.
--seconds-between-progress-updates	10.0	Output traversal statistics every time this many seconds elapse
--sequence-dictionary	null	Use the given sequence dictionary as the master/canonical sequence dictionary. Must be a .dict file.
--tmp-dir	null	Temp directory to use.
--use-jdk-deflater  -jdk-deflater	false	Whether to use the JdkDeflater (as opposed to IntelDeflater)
--use-jdk-inflater  -jdk-inflater	false	Whether to use the JdkInflater (as opposed to IntelInflater)
--verbosity	INFO	Control verbosity of logging.
Advanced Arguments
--showHidden	false	display hidden arguments

Argument details

Arguments in this list are specific to this tool. Keep in mind that other arguments are available that are shared with other tools (e.g. command-line GATK arguments); see Inherited arguments above.

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--add-output-sam-program-record / -add-output-sam-program-record

If true, adds a PG tag to created SAM/BAM/CRAM files.

boolean  true

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--add-output-vcf-command-line / -add-output-vcf-command-line

If true, adds a command line header line to created VCF files.

boolean  true

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--arguments_file / NA

read one or more arguments files and add them to the command line

List[File]  []

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--cloud-index-prefetch-buffer / -CIPB

Size of the cloud-only prefetch buffer (in MB; 0 to disable). Defaults to cloudPrefetchBuffer if unset.

int  -1  [ [ -∞  ∞ ] ]

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--cloud-prefetch-buffer / -CPB

Size of the cloud-only prefetch buffer (in MB; 0 to disable).

int  40  [ [ -∞  ∞ ] ]

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--create-output-bam-index / -OBI

If true, create a BAM/CRAM index when writing a coordinate-sorted BAM/CRAM file.

boolean  true

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--create-output-bam-md5 / -OBM

If true, create a MD5 digest for any BAM/SAM/CRAM file created

boolean  false

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--create-output-variant-index / -OVI

If true, create a VCF index when writing a coordinate-sorted VCF file.

boolean  true

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--create-output-variant-md5 / -OVM

If true, create a a MD5 digest any VCF file created.

boolean  false

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--disable-bam-index-caching / -DBIC

If true, don't cache bam indexes, this will reduce memory requirements but may harm performance if many intervals are specified. Caching is automatically disabled if there are no intervals specified.

boolean  false

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--disable-read-filter / -DF

Read filters to be disabled before analysis

List[String]  []

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--disable-sequence-dictionary-validation / -disable-sequence-dictionary-validation

If specified, do not check the sequence dictionaries from our inputs for compatibility. Use at your own risk!

boolean  false

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--disable-tool-default-read-filters / -disable-tool-default-read-filters

Disable all tool default read filters (WARNING: many tools will not function correctly without their default read filters on)

boolean  false

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--exclude-intervals / -XL

One or more genomic intervals to exclude from processing
Use this argument to exclude certain parts of the genome from the analysis (like -L, but the opposite). This argument can be specified multiple times. You can use samtools-style intervals either explicitly on the command line (e.g. -XL 1 or -XL 1:100-200) or by loading in a file containing a list of intervals (e.g. -XL myFile.intervals).

List[String]  []

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--gatk-config-file / NA

A configuration file to use with the GATK.

String  null

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--gcs-max-retries / -gcs-retries

If the GCS bucket channel errors out, how many times it will attempt to re-initiate the connection

int  20  [ [ -∞  ∞ ] ]

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--gcs-project-for-requester-pays / NA

Project to bill when accessing "requester pays" buckets. If unset, these buckets cannot be accessed.

String  ""

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--help / -h

display the help message

boolean  false

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--input / -I

BAM/SAM/CRAM file containing reads

List[String]  []

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--interval-exclusion-padding / -ixp

Amount of padding (in bp) to add to each interval you are excluding.
Use this to add padding to the intervals specified using -XL. For example, '-XL 1:100' with a padding value of 20 would turn into '-XL 1:80-120'. This is typically used to add padding around targets when analyzing exomes.

int  0  [ [ -∞  ∞ ] ]

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--interval-merging-rule / -imr

Interval merging rule for abutting intervals
By default, the program merges abutting intervals (i.e. intervals that are directly side-by-side but do not actually overlap) into a single continuous interval. However you can change this behavior if you want them to be treated as separate intervals instead.

The --interval-merging-rule argument is an enumerated type (IntervalMergingRule), which can have one of the following values:

ALL

OVERLAPPING_ONLY

IntervalMergingRule  ALL

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--interval-padding / -ip

Amount of padding (in bp) to add to each interval you are including.
Use this to add padding to the intervals specified using -L. For example, '-L 1:100' with a padding value of 20 would turn into '-L 1:80-120'. This is typically used to add padding around targets when analyzing exomes.

int  0  [ [ -∞  ∞ ] ]

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--interval-set-rule / -isr

Set merging approach to use for combining interval inputs
By default, the program will take the UNION of all intervals specified using -L and/or -XL. However, you can change this setting for -L, for example if you want to take the INTERSECTION of the sets instead. E.g. to perform the analysis only on chromosome 1 exomes, you could specify -L exomes.intervals -L 1 --interval-set-rule INTERSECTION. However, it is not possible to modify the merging approach for intervals passed using -XL (they will always be merged using UNION). Note that if you specify both -L and -XL, the -XL interval set will be subtracted from the -L interval set.

The --interval-set-rule argument is an enumerated type (IntervalSetRule), which can have one of the following values:

UNION

Take the union of all intervals

INTERSECTION

Take the intersection of intervals (the subset that overlaps all intervals specified)

IntervalSetRule  UNION

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--intervals / -L

One or more genomic intervals over which to operate

List[String]  []

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--lenient / -LE

Lenient processing of VCF files

boolean  false

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--line-width / NA

Maximum length of sequence to write per line

int  60  [ [ -∞  ∞ ] ]

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--output / -O

Path to write the output fasta to

R String  null

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--QUIET / NA

Whether to suppress job-summary info on System.err.

Boolean  false

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--read-filter / -RF

Read filters to be applied before analysis

List[String]  []

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--read-index / -read-index

Indices to use for the read inputs. If specified, an index must be provided for every read input and in the same order as the read inputs. If this argument is not specified, the path to the index for each input will be inferred automatically.

List[String]  []

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--read-validation-stringency / -VS

Validation stringency for all SAM/BAM/CRAM/SRA files read by this program. The default stringency value SILENT can improve performance when processing a BAM file in which variable-length data (read, qualities, tags) do not otherwise need to be decoded.

The --read-validation-stringency argument is an enumerated type (ValidationStringency), which can have one of the following values:

STRICT

LENIENT

SILENT

ValidationStringency  SILENT

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--reference / -R

Reference sequence file

R String  null

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--seconds-between-progress-updates / -seconds-between-progress-updates

Output traversal statistics every time this many seconds elapse

double  10.0  [ [ -∞  ∞ ] ]

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--sequence-dictionary / -sequence-dictionary

Use the given sequence dictionary as the master/canonical sequence dictionary. Must be a .dict file.

String  null

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--showHidden / -showHidden

display hidden arguments

boolean  false

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--sites-only-vcf-output / NA

If true, don't emit genotype fields when writing vcf file output.

boolean  false

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--snp-mask / NA

SNP mask VCF file
SNPs from this file are used as a mask (inserting N's in the sequence) when constructing the alternate reference

FeatureInput[VariantContext]  null

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--snp-mask-priority / NA

Give the snp mask priority over the input VCF.
Gives priority to a SNP mask over an input VCF for a site. Only has an effect if the --snp-mask argument is used.

boolean  false

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--tmp-dir / NA

Temp directory to use.

GATKPathSpecifier  null

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--use-iupac-sample / NA

If specified, heterozygous SNP sites will be output using IUPAC ambiguity codes given the genotypes for this sample
This option will generate an error if the specified sample does not exist in the VCF. Non-diploid (or non-called) genotypes are ignored.

String  null

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--use-jdk-deflater / -jdk-deflater

Whether to use the JdkDeflater (as opposed to IntelDeflater)

boolean  false

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--use-jdk-inflater / -jdk-inflater

Whether to use the JdkInflater (as opposed to IntelInflater)

boolean  false

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--variant / -V

A source of variants to merge with the reference sequence.
Variants from this input file are used by this tool to construct an alternate reference.

R FeatureInput[VariantContext]  null

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--verbosity / -verbosity

Control verbosity of logging.

The --verbosity argument is an enumerated type (LogLevel), which can have one of the following values:

ERROR

WARNING

INFO

DEBUG

LogLevel  INFO

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--version / NA

display the version number for this tool

boolean  false

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GATK version 4.1.6.0-SNAPSHOT built at Thu, 2 Apr 2020 14:54:17 -0400.