Complex data structure------Hash

use Data::Dumper;
%relatedgenes=();
$relatedgenes{'one'}=[1,2,3,4];
$relatedgenes{'two'}=[12,13,14,10];
push @{$relatedgenes{'two'}},'2121';

print Dumper(\%relatedgenes);

$VAR1 = {
          'one' => [
                     1,
                     2,
                     3,
                     4
                   ],
          'two' => [
                     12,
                     13,
                     14,
                     10,
                     '2121'
                   ]
        };