#!/usr/bin/perl -w use strict; my $filename; my $accession_id; my %accession; my $gene_Name; print "Please enter in the filename: "; chomp($filename = ); print "Please enter in the accession_ID: "; chomp($accession_id = ); open(FILENAME, $filename) or die "cannot open file: $! "; while($_ = ) { if ($_ =~ />gi/) { $gene_Name = $_; } else { } $accession{$gene_Name} .= $_; } foreach $gene_Name (keys %accession) { if ($gene_Name =~ /$accession_id/i) { print "$accession{$gene_Name}\n"; } }