                                equicktandem



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Function

   Find tandem repeats in nucleotide sequences

Description

   equicktandem identifies regions in a nucleotide sequence which are
   likely to contain tanden repeats. For a region to be reported, it must
   be no larger than a specified maximum repeat size and must score higher
   than a threshold score, which is also user-specified. The output is a
   standard EMBOSS report file with details of the location and score of
   any potential tandem repeats. Optionally, the output can be written in
   the format of the Sanger Centre quicktandem program.

Algorithm

   equicktandem looks for sequence segments in which each base tends to
   match the base a fixed number ('repeatsize') of nucleotides back in the
   sequence, i.e. with an autocorrelation peak at 'repeatsize'. The score
   for a segment is the sum of the scores for each position in that
   segment: the score is incremented (+1) for a match to the corresponding
   base 'repeatsize' back and decremented (-1) for a mismatch. The
   algorithm allows for drift in the repeating sequence, i.e. exact
   matches are not required, nor is a consensus sequence for the whole
   repeat block used (that is what etandem does). The algorithm does not
   account for gaps but it is much quicker than etandem.

Usage

   Here is a sample session with equicktandem

   The input sequence is the human herpesvirus tandem repeat.


% equicktandem -noorigfile
Find tandem repeats in nucleotide sequences
Input nucleotide sequence: tembl:L46634
Maximum repeat size [600]:
Threshold score [20]:
Output report [l46634.qtan]:


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

Command line arguments

Find tandem repeats in nucleotide sequences
Version: EMBOSS:6.5.6.0

   Standard (Mandatory) qualifiers:
  [-sequence]          sequence   Nucleotide sequence filename and optional
                                  format, or reference (input USA)
   -maxrepeat          integer    [600] Maximum repeat size (Any integer
                                  value)
   -threshold          integer    [20] Threshold score (Any integer value)
  [-outfile]           report     [*.equicktandem] Output report file name
                                  (default -rformat table)

   Additional (Optional) qualifiers: (none)
   Advanced (Unprompted) qualifiers:
   -origfile           outfile    [*.equicktandem] Sanger Centre program
                                  quicktandem output file (optional)

   Associated qualifiers:

   "-sequence" associated qualifiers
   -sbegin1            integer    Start of the sequence to be used
   -send1              integer    End of the 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
   -scircular1         boolean    Sequence is circular
   -sformat1           string     Input sequence format
   -iquery1            string     Input query fields or ID list
   -ioffset1           integer    Input start position offset
   -sdbname1           string     Database name
   -sid1               string     Entryname
   -ufo1               string     UFO features
   -fformat1           string     Features format
   -fopenfile1         string     Features file name

   "-outfile" associated qualifiers
   -rformat2           string     Report format
   -rname2             string     Base file name
   -rextension2        string     File name extension
   -rdirectory2        string     Output directory
   -raccshow2          boolean    Show accession number in the report
   -rdesshow2          boolean    Show description in the report
   -rscoreshow2        boolean    Show the score in the report
   -rstrandshow2       boolean    Show the nucleotide strand in the report
   -rusashow2          boolean    Show the full USA in the report
   -rmaxall2           integer    Maximum total hits to report
   -rmaxseq2           integer    Maximum hits to report for one sequence

   "-origfile" associated qualifiers
   -odirectory         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 and exit. 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
   -version            boolean    Report version number and exit


Input file format

   equicktandem reads a single nucleotide sequence.

   The input is a standard EMBOSS sequence query (also known as a 'USA').

   Major sequence database sources defined as standard in EMBOSS
   installations include srs:embl, srs:uniprot and ensembl

   Data can also be read from sequence output in any supported format
   written by an EMBOSS or third-party application.

   The input format can be specified by using the command-line qualifier
   -sformat xxx, where 'xxx' is replaced by the name of the required
   format. The available format names are: gff (gff3), gff2, embl (em),
   genbank (gb, refseq), ddbj, refseqp, pir (nbrf), swissprot (swiss, sw),
   dasgff and debug.

   See: http://emboss.sf.net/docs/themes/SequenceFormats.html for further
   information on sequence formats.

  Input files for usage example

   'tembl:L46634' is a sequence entry in the example nucleic acid database
   'tembl'

  Database entry: tembl:L46634

ID   L46634; SV 1; linear; genomic DNA; STD; VRL; 1272 BP.
XX
AC   L46634; L46689;
XX
DT   06-NOV-1995 (Rel. 45, Created)
DT   04-MAR-2000 (Rel. 63, Last updated, Version 3)
XX
DE   Human herpesvirus 7 (clone ED132'1.2) telomeric repeat region.
XX
KW   telomeric repeat.
XX
OS   Human herpesvirus 7
OC   Viruses; dsDNA viruses, no RNA stage; Herpesvirales; Herpesviridae;
OC   Betaherpesvirinae; Roseolovirus.
XX
RN   [1]
RP   1-1272
RX   PUBMED; 7494318.
RA   Secchiero P., Nicholas J., Deng H., Xiaopeng T., van Loon N., Ruvolo V.R.,
RA   Berneman Z.N., Reitz M.S.Jr., Dewhurst S.;
RT   "Identification of human telomeric repeat motifs at the genome termini of
RT   human herpesvirus 7: structural analysis and heterogeneity";
RL   J. Virol. 69(12):8041-8045(1995).
XX
FH   Key             Location/Qualifiers
FH
FT   source          1..1272
FT                   /organism="Human herpesvirus 7"
FT                   /strain="JI"
FT                   /mol_type="genomic DNA"
FT                   /clone="ED132'1.2"
FT                   /db_xref="taxon:10372"
FT   repeat_region   207..928
FT                   /note="long and complex repeat region composed of various
FT                   direct repeats, including TAACCC (TRS), degenerate copies
FT                   of TRS motifs and a 14-bp repeat, TAGGGCTGCGGCCC"
FT   misc_signal     938..998
FT                   /note="pac2 motif"
FT   misc_feature    1009
FT                   /note="right genome terminus (...ACA)"
XX
SQ   Sequence 1272 BP; 346 A; 455 C; 222 G; 249 T; 0 other;
     aagcttaaac tgaggtcaca cacgacttta attacggcaa cgcaacagct gtaagctgca        60
     ggaaagatac gatcgtaagc aaatgtagtc ctacaatcaa gcgaggttgt agacgttacc       120
     tacaatgaac tacacctcta agcataacct gtcgggcaca gtgagacacg cagccgtaaa       180
     ttcaaaactc aacccaaacc gaagtctaag tctcacccta atcgtaacag taaccctaca       240
     actctaatcc tagtccgtaa ccgtaacccc aatcctagcc cttagcccta accctagccc       300
     taaccctagc tctaacctta gctctaactc tgaccctagg cctaacccta agcctaaccc       360
     taaccgtagc tctaagttta accctaaccc taaccctaac catgaccctg accctaaccc       420
     tagggctgcg gccctaaccc tagccctaac cctaacccta atcctaatcc tagccctaac       480
     cctagggctg cggccctaac cctagcccta accctaaccc taaccctagg gctgcggccc       540
     taaccctaac cctagggctg cggcccgaac cctaacccta accctaaccc taaccctagg       600
     gctgcggccc taaccctaac cctagggctg cggccctaac cctaacccta gggctgcggc       660
     ccgaacccta accctaaccc taaccctagg gctgcggccc taaccctaac cctagggctg       720
     cggccctaac cctaacccta actctagggc tgcggcccta accctaaccc taaccctaac       780
     cctagggctg cggcccgaac cctagcccta accctaaccc tgaccctgac cctaacccta       840
     accctaaccc taaccctaac cctaacccta accctaaccc taaccctaac cctaacccta       900
     accctaaccc taaccctaac cctaaccccg cccccactgg cagccaatgt cttgtaatgc       960
     cttcaaggca ctttttctgc gagccgcgcg cagcactcag tgaaaaacaa gtttgtgcac      1020
     gagaaagacg ctgccaaacc gcagctgcag catgaaggct gagtgcacaa ttttggcttt      1080
     agtcccataa aggcgcggct tcccgtagag tagaaaaccg cagcgcggcg cacagagcga      1140
     aggcagcggc tttcagactg tttgccaagc gcagtctgca tcttaccaat gatgatcgca      1200
     agcaagaaaa atgttctttc ttagcatatg cgtggttaat cctgttgtgg tcatcactaa      1260
     gttttcaagc tt                                                          1272
//

Output file format

   The output is a standard EMBOSS report file.

   The results can be output in one of several styles by using the
   command-line qualifier -rformat xxx, where 'xxx' is replaced by the
   name of the required format. The available format names are: embl,
   genbank, gff, pir, swiss, dasgff, debug, listfile, dbmotif, diffseq,
   draw, restrict, excel, feattable, motif, nametable, regions, seqtable,
   simple, srs, table, tagseq.

   See: http://emboss.sf.net/docs/themes/ReportFormats.html for further
   information on report formats.

   By default equicktandem writes a 'table' report file.

  Output files for usage example

  File: l46634.qtan

########################################
# Program: equicktandem
# Rundate: Sun 15 Jul 2012 12:00:00
# Commandline: equicktandem
#    -noorigfile
#    -sequence tembl:L46634
# Report_format: table
# Report_file: l46634.qtan
########################################

#=======================================
#
# Sequence: L46634     from: 1   to: 1272
# HitCount: 1
#
# Threshold: 20
# Maxrepeat: 600
#
#=======================================

  Start     End  Strand   Score   Size  Count
    191     935       +     339      6    124

#---------------------------------------
#---------------------------------------

Data files

   None.

Notes

   A tandem repeat in a DNA sequence is where a sequence of two or more
   nucleotides is repeated without any intervening nucleotides. For
   example "GATACAGATACAGATACA" is a tandem repeat of "GATACA". A short
   tandem repeat is typically 2 to 10 base pairs and occur in introns. The
   sequence and number of repeats at a given locus tend to be
   characteristic of an individual. Where enough STR loci are examined, a
   unique genetic profile of an individual can be built. Thus, tandem
   repeats are useful for genotyping, for example, in determining
   parentage and in forensic cases.

   To identify genuine tandem repeats, the repeat sizes and / or sequence
   regions identified by equicktandem can be used as input to etandem.
   etandem will confirm which regions are true tandem repeats and give an
   accurate specification of the repeats.

References

   None.

Warnings

   None.

Diagnostic Error Messages

   None.

Exit status

   It always exits with a status of 0.

Known bugs

   None.

See also

                    Program name                   Description
                    einverted    Find inverted repeats in nucleotide sequences
                    etandem      Find tandem repeats in a nucleotide sequence
                    palindrome   Find inverted repeats in nucleotide sequence(s)

Author(s)

                    This program was originally written by Richard Durbin
   Sanger           Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge,
                    CB10 1SA, UK.

                    Please report all bugs to the EMBOSS bug team
                    (emboss-bug (c) emboss.open-bio.org) not to the original author.

                    This application was modified for inclusion in EMBOSS by Peter Rice
   European         Bioinformatics Institute, Wellcome Trust Genome Campus,
   Hinxton,         Cambridge CB10 1SD, UK

                    Please report all bugs to the EMBOSS bug team
                    (emboss-bug (c) emboss.open-bio.org) not to the original author.

History

                    Completed 25 May 1999

Target users

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

Comments

                    None
