visit http://bioperl.org. install recent BioPerl 1.4 package and you will have examples. Read this http://search.cpan.org/~birney/bioperl-run-1.4/Bio/Tools/Run/PiseApplication/codonw.pm and see also: http://bioweb.pasteur.fr/seqanal/interfaces/codonw.html hope helps, Viren Konde

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