#!/usr/bin/perl -w
use strict;
my %genome1 = (
   a => [ 10, 15 ],
   b => [  3,  7 ],
   c => [  9, 14 ],
);

my %genome2 = (
   d => [  3, 21 ],
   a => [  3,  4 ],
   g => [  5, 10 ],
   b => [  2,  7 ],
);

for (keys(%genome1)) {
   if ($genome2{$_}) {
      print("$genome1{$_} and $genome2{$_}\n");
   }
}