extractalign

 

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Function

Extract regions from a sequence alignment

Description

extractalign allows you to specify one or more regions of a sequence alignment to extract sub-sequences from to build up a resulting sub-sequence alignment. extractakign reads in a sequence alignment and a set of regions of that alignment as specified by pairs of start and end positions (either on the command-line or contained in a file) using gapped alignment positions as the coordinates, and writes out the specified regions of the input sequence in the order in which they have been specified. Thus, if the sequence "AAAGGGTTT" has been input and the regions: "7-9, 3-4" have been specified, then the output sequence will be: "TTTAG".

Usage

Here is a sample session with extractalign

Extract the region from position 10 to 20:


% extractalign dna.msf result.seq -regions '11-30' 
Extract regions from a sequence alignment

Go to the input files for this example
Go to the output files for this example

Command line arguments

   Standard (Mandatory) qualifiers:
  [-sequence]          seqset     (Aligned) sequence set filename and optional
                                  format, or reference (input USA)
   -regions            range      [Whole sequence] Regions to extract.
                                  A set of regions is specified by a set of
                                  pairs of positions.
                                  The positions are integers.
                                  They are separated by any non-digit,
                                  non-alpha character.
                                  Examples of region specifications are:
                                  24-45, 56-78
                                  1:45, 67=99;765..888
                                  1,5,8,10,23,45,57,99
  [-outseq]            seqoutall  [.] Sequence set(s)
                                  filename and optional format (output USA)

   Additional (Optional) qualifiers: (none)
   Advanced (Unprompted) qualifiers: (none)
   Associated qualifiers:

   "-sequence" associated qualifiers
   -sbegin1            integer    Start of each sequence to be used
   -send1              integer    End of each sequence to be used
   -sreverse1          boolean    Reverse (if DNA)
   -sask1              boolean    Ask for begin/end/reverse
   -snucleotide1       boolean    Sequence is nucleotide
   -sprotein1          boolean    Sequence is protein
   -slower1            boolean    Make lower case
   -supper1            boolean    Make upper case
   -sformat1           string     Input sequence format
   -sdbname1           string     Database name
   -sid1               string     Entryname
   -ufo1               string     UFO features
   -fformat1           string     Features format
   -fopenfile1         string     Features file name

   "-outseq" associated qualifiers
   -osformat2          string     Output seq format
   -osextension2       string     File name extension
   -osname2            string     Base file name
   -osdirectory2       string     Output directory
   -osdbname2          string     Database name to add
   -ossingle2          boolean    Separate file for each entry
   -oufo2              string     UFO features
   -offormat2          string     Features format
   -ofname2            string     Features file name
   -ofdirectory2       string     Output directory

   General qualifiers:
   -auto               boolean    Turn off prompts
   -stdout             boolean    Write first file to standard output
   -filter             boolean    Read first file from standard input, write
                                  first file to standard output
   -options            boolean    Prompt for standard and additional values
   -debug              boolean    Write debug output to program.dbg
   -verbose            boolean    Report some/full command line options
   -help               boolean    Report command line options. More
                                  information on associated and general
                                  qualifiers can be found with -help -verbose
   -warning            boolean    Report warnings
   -error              boolean    Report errors
   -fatal              boolean    Report fatal errors
   -die                boolean    Report dying program messages

Standard (Mandatory) qualifiers Allowed values Default
[-sequence]
(Parameter 1)
(Aligned) sequence set filename and optional format, or reference (input USA) Readable set of sequences Required
-regions Regions to extract. A set of regions is specified by a set of pairs of positions. The positions are integers. They are separated by any non-digit, non-alpha character. Examples of region specifications are: 24-45, 56-78 1:45, 67=99;765..888 1,5,8,10,23,45,57,99 Sequence range Whole sequence
[-outseq]
(Parameter 2)
Sequence set(s) filename and optional format (output USA) Writeable sequence(s) <*>.format
Additional (Optional) qualifiers Allowed values Default
(none)
Advanced (Unprompted) qualifiers Allowed values Default
(none)

Input file format

extractalign reads a normal sequence USA.

Input files for usage example

File: dna.msf

!!NA_MULTIPLE_ALIGNMENT

 dna.msf  MSF: 120  Type: N  January 01, 1776  12:00  Check: 3196 ..

 Name: MSFM1          Len:   120  Check:  8587  Weight:  1.00
 Name: MSFM2          Len:   120  Check:  6178  Weight:  1.00
 Name: MSFM3          Len:   120  Check:  8431  Weight:  1.00

//

        MSFM1  ACGTACGTAC GTACGTACGT ACGTACGTAC GTACGTACGT ACGTACGTAC
        MSFM2  ACGTACGTAC GTACGTACGT ....ACGTAC GTACGTACGT ACGTACGTAC
        MSFM3  ACGTACGTAC GTACGTACGT ACGTACGTAC GTACGTACGT CGTACGTACG

        MSFM1  GTACGTACGT ACGTACGTAC GTACGTACGT ACGTACGTAC GTACGTACGT
        MSFM2  GTACGTACGT ACGTACGTAC GTACGTACGT ACGTACGTAC GTACGTACGT
        MSFM3  TACGTACGTA CGTACGTACG TACGTACGTA ACGTACGTAC GTACGTACGT

        MSFM1  ACGTACGTAC GTACGTACGT
        MSFM2  ACGTACGTTG CAACGTACGT
        MSFM3  ACGTACGTAC GTACGTACGT

You can specifiy a file of ranges to extract by giving the '-regions' qualifier the value '@' followed by the name of the file containing the ranges. (eg: '-regions @myfile').

The format of the range file is:

An example range file is:


# this is my set of ranges
12   23
 4   5       this is like 12-23, but smaller
67   10348   interesting region

Output file format

The output is a normal sequence file.

Output files for usage example

File: result.seq

>MSFM1
GTACGTACGTACGTACGTAC
>MSFM2
GTACGTACGT----ACGTAC
>MSFM3
GTACGTACGTACGTACGTAC

If the option '-separate' is used then each specified region is written to the output file as a separate sequence. The name of the sequence is created from the name of the original sequence with the start and end positions of the range appended with underscore characters between them,

For example: "XYZ region 2 to 34" is written as: "XYZ_2_34"

Data files

None.

Notes

None.

References

None.

Warnings

None.

Diagnostic Error Messages

Several warning messages about malformed region specifications:

Exit status

It exits with status 0, unless a region is badly constructed.

Known bugs

None noted.

Comments

See also

Program name Description
aligncopy Reads and writes alignments
aligncopypair Reads and writes pairs from alignments
biosed Replace or delete sequence sections
codcopy Copy and reformat a codon usage table
cutseq Removes a section from a sequence
degapseq Removes non-alphabetic (e.g. gap) characters from sequences
descseq Alter the name or description of a sequence
entret Retrieves sequence entries from flatfile databases and files
extractfeat Extract features from sequence(s)
extractseq Extract regions from a sequence
featcopy Reads and writes a feature table
featreport Reads and writes a feature table
listor Write a list file of the logical OR of two sets of sequences
makenucseq Create random nucleotide sequences
makeprotseq Create random protein sequences
maskambignuc Masks all ambiguity characters in nucleotide sequences with N
maskambigprot Masks all ambiguity characters in protein sequences with X
maskfeat Write a sequence with masked features
maskseq Write a sequence with masked regions
newseq Create a sequence file from a typed-in sequence
nohtml Remove mark-up (e.g. HTML tags) from an ASCII text file
noreturn Remove carriage return from ASCII files
nospace Remove all whitespace from an ASCII text file
notab Replace tabs with spaces in an ASCII text file
notseq Write to file a subset of an input stream of sequences
nthseq Write to file a single sequence from an input stream of sequences
nthseqset Reads and writes (returns) one set of sequences from many
pasteseq Insert one sequence into another
revseq Reverse and complement a nucleotide sequence
seqret Reads and writes (returns) sequences
seqretsetall Reads and writes (returns) many sets of sequences
seqretsplit Reads sequences and writes them to individual files
sizeseq Sort sequences by size
skipredundant Remove redundant sequences from an input set
skipseq Reads and writes (returns) sequences, skipping first few
splitsource Split sequence(s) into original source sequences
splitter Split sequence(s) into smaller sequences
trimest Remove poly-A tails from nucleotide sequences
trimseq Remove unwanted characters from start and end of sequence(s)
trimspace Remove extra whitespace from an ASCII text file
union Concatenate multiple sequences into a single sequence
vectorstrip Removes vectors from the ends of nucleotide sequence(s)
yank Add a sequence reference (a full USA) to a list file

Author(s)

Peter Rice (pmr © ebi.ac.uk)
European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK

History

Target users

This program is intended to be used by everyone and everything, from naive users to embedded scripts.

Comments

None