%Hash1
key 1 => '1'
key 15 => '3'
key 150 => '1'
##</code><code>##

%Hash2
key 1 => '1'
key 15 => '1'
key 140 => '1'
##</code><code>##

%CombinedHash
key 1 => '2'
key 15 => '4'
key 140 => '1'
key 150 => '1'
##</code><code>##

my %muthash = (
        key1 => '1',
        key15 => '3',
        key150 => '1', );
my %copyhash (
        key1 => '1',
        key15 => '1',
        key140 => '1', );
my %mergedhash;
%mergedhash = map {$_=> $muthash{$_} + $copyhash{$_} } (keys %muthash,keys %copyhash);

##</code><code>##

my $fileoutput = $name." COMB".".csv";		
open (OUTPUT,">Input/$fileoutput") or die "Could not open output file\n";
foreach my $gene (keys %mergedhash) {
	print OUTPUT "$gene",",","$mergedhash{$gene}","\n";
}
close (OUTPUT);