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Calculate fractional GC content of nucleic acid sequences


geecee calculates the fraction of G+C bases of the input nucleic acid sequence(s). It sums the number of G and C bases in the input sequence(s) and writes the result to file as the fraction (in the interval 0.0 to 1.0) of the length of the whole sequence.


Here is a sample session with geecee

% geecee tembl:L46634 
Calculate fractional GC content of nucleic acid sequences
Output file [l46634.geecee]: 

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

Command line arguments

   Standard (Mandatory) qualifiers:
  [-sequence]          seqall     Nucleotide sequence(s) filename and optional
                                  format, or reference (input USA)
  [-outfile]           outfile    [*.geecee] Output file name

   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

   "-outfile" associated qualifiers
   -odirectory2        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
(Parameter 1)
Nucleotide sequence(s) filename and optional format, or reference (input USA) Readable sequence(s) Required
(Parameter 2)
Output file name Output file <*>.geecee
Additional (Optional) qualifiers Allowed values Default
Advanced (Unprompted) qualifiers Allowed values Default

Input file format

geecee reads any nucleic acid sequence USAs.

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.
AC   L46634; L46689;
DT   06-NOV-1995 (Rel. 45, Created)
DT   04-MAR-2000 (Rel. 63, Last updated, Version 3)
DE   Human herpesvirus 7 (clone ED132'1.2) telomeric repeat region.
KW   telomeric repeat.
OS   Human herpesvirus 7
OC   Viruses; dsDNA viruses, no RNA stage; Herpesvirales; Herpesviridae;
OC   Betaherpesvirinae; Roseolovirus.
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).
FH   Key             Location/Qualifiers
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)"
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

Output files for usage example

File: l46634.geecee

#Sequence   GC content
L46634        0.53

The first non-blank line is the title line. Subsequent lines consist of two columns of data.

Data files








Diagnostic Error Messages


Exit status

0 on successful completion.

Known bugs


See also

Program name Description
cpgplot Identify and plot CpG islands in nucleotide sequence(s)
cpgreport Identify and report CpG-rich regions in nucleotide sequence(s)
newcpgreport Identify CpG islands in nucleotide sequence(s)
newcpgseek Identify and report CpG-rich regions in nucleotide sequence(s)


Richard Bruskiewich (
while he was at:
Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.


Completed 18th June 1999.

Target users

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


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