Left align and trim vairants
This tool takes a VCF file, left-aligns the indels and trims common bases from indels, leaving them with a minimum representation. The same indel can often be placed at multiple positions and still represent the same haplotype. While the standard convention with VCF is to place an indel at the left-most position this isn't always done, so this tool can be used to left-align them. This tool optionally splits multiallelic sites into biallelics and left-aligns individual alleles. Optionally, the tool will not trim common bases from indels.
A variant call set to left-align and trim.
A left-aligned VCF.
gatk LeftAlignAndTrimVariants \ -R reference.fasta \ -V input.vcf \ -O output.vcf
gatk LeftAlignAndTrimVariants \ -R reference.fasta \ -V input.vcf \ -O output.vcf \ --dont-trim-alleles
gatk LeftAlignAndTrimVariants \ -R reference.fasta \ -V input.vcf \ -O output.vcf \ --max-indel-length 208
gatk LeftAlignAndTrimVariants \ -R reference.fasta \ -V input.vcf \ -O output.vcf \ --split-multi-allelics
gatk LeftAlignAndTrimVariants \ -R reference.fasta \ -V input.vcf \ -O output.vcf \ --split-multi-allelics \ --dont-trim-alleles --keep-original-ac
gatk LeftAlignAndTrimVariants \ -R reference.fasta \ -V input.vcf \ -O output.vcf \ --max-leading-bases 2000
This Read Filter is automatically applied to the data by the Engine before processing by LeftAlignAndTrimVariants.
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 | File to which variants should be written | |
--reference -R |
null | Reference sequence file | |
--variant -V |
null | A VCF file containing variants | |
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! | |
--dont-trim-alleles -no-trim |
false | Do not Trim alleles to remove bases common to all of them | |
--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 | |
--keep-original-ac |
false | Store the original AC, AF, and AN values after subsetting | |
--max-indel-length |
200 | Set maximum indel size to realign | |
--max-leading-bases |
1000 | Set max reference window size to look back before allele | |
--sites-only-vcf-output |
false | If true, don't emit genotype fields when writing vcf file output. | |
--split-multi-allelics |
false | Split multiallelic records and left-align individual alleles | |
--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 |
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.
If true, adds a PG tag to created SAM/BAM/CRAM files.
boolean true
If true, adds a command line header line to created VCF files.
boolean true
read one or more arguments files and add them to the command line
List[File] []
Size of the cloud-only prefetch buffer (in MB; 0 to disable). Defaults to cloudPrefetchBuffer if unset.
int -1 [ [ -∞ ∞ ] ]
Size of the cloud-only prefetch buffer (in MB; 0 to disable).
int 40 [ [ -∞ ∞ ] ]
If true, create a BAM/CRAM index when writing a coordinate-sorted BAM/CRAM file.
boolean true
If true, create a MD5 digest for any BAM/SAM/CRAM file created
boolean false
If true, create a VCF index when writing a coordinate-sorted VCF file.
boolean true
If true, create a a MD5 digest any VCF file created.
boolean 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.
boolean false
Read filters to be disabled before analysis
List[String] []
If specified, do not check the sequence dictionaries from our inputs for compatibility. Use at your own risk!
boolean false
Disable all tool default read filters (WARNING: many tools will not function correctly without their default read filters on)
boolean false
Do not Trim alleles to remove bases common to all of them
If this argument is set, bases common to all alleles will not be removed and will not leave their minimal representation.
boolean false
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] []
A configuration file to use with the GATK.
String null
If the GCS bucket channel errors out, how many times it will attempt to re-initiate the connection
int 20 [ [ -∞ ∞ ] ]
Project to bill when accessing "requester pays" buckets. If unset, these buckets cannot be accessed.
String ""
display the help message
boolean false
BAM/SAM/CRAM file containing reads
List[String] []
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 [ [ -∞ ∞ ] ]
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:
IntervalMergingRule ALL
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 [ [ -∞ ∞ ] ]
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:
IntervalSetRule UNION
One or more genomic intervals over which to operate
List[String] []
Store the original AC, AF, and AN values after subsetting
When subsetting a callset, this tool recalculates the AC, AF, and AN values corresponding to the contents of the
subset. If this flag is enabled, the original values of those annotations will be stored in new annotations called
AC_Orig, AF_Orig, and AN_Orig.
boolean false
Lenient processing of VCF files
boolean false
Set maximum indel size to realign
Maximum indel size to realign. Indels larger than this will be left unadjusted.
int 200 [ [ -∞ ∞ ] ]
Set max reference window size to look back before allele
Distance in reference to look back before allele
int 1000 [ [ -∞ ∞ ] ]
File to which variants should be written
Output file to which to write left aligned variants
R File null
Whether to suppress job-summary info on System.err.
Boolean false
Read filters to be applied before analysis
List[String] []
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] []
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:
ValidationStringency SILENT
Reference sequence file
R String null
Output traversal statistics every time this many seconds elapse
double 10.0 [ [ -∞ ∞ ] ]
Use the given sequence dictionary as the master/canonical sequence dictionary. Must be a .dict file.
String null
display hidden arguments
boolean false
If true, don't emit genotype fields when writing vcf file output.
boolean false
Split multiallelic records and left-align individual alleles
If this argument is set, split multiallelic records and left-align individual alleles.
If this argument is not set, multiallelic records are not attempted to left-align and will be copied as is.
boolean false
Temp directory to use.
GATKPathSpecifier null
Whether to use the JdkDeflater (as opposed to IntelDeflater)
boolean false
Whether to use the JdkInflater (as opposed to IntelInflater)
boolean false
A VCF file containing variants
R String null
Control verbosity of logging.
The --verbosity argument is an enumerated type (LogLevel), which can have one of the following values:
LogLevel INFO
display the version number for this tool
boolean false
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GATK version 4.1.4.0 built at Wed, 9 Oct 2019 15:19:59 -0400.