use strict;
use warnings;

my ($mio, $mio2);     
my @array_with_all_fields=();
my $match = 'DOID:2055';
unlink ("myoutputfilename6.txt");
unlink ("myoutputfilename7.txt");
open(my $file, '<', 'do_human_mapping.gmt') or die "open: $!";

open my $out_file3, '>', 'myoutputfilename6.txt' or die "$!"; 
open my $out_file4, '>', 'myoutputfilename7.txt' or die "$!"; 

while (<$file>){
  my ($name,$id,@genes) = split /\t/;
  if ($id eq $match) {
     $mio= join("\n",@genes);
     print $mio."\n";

     print $out_file3 $mio."\n"; # print on file
  }
  if (grep/^$match$/, @genes){
       $mio2=$id;
       print $mio2."\n";

       print $out_file4 $mio2."\n"; # print on file
   }
}