my @values;
my %labels;

foreach(1..10)
{
  $values[$_] = $_;
  $labels{$_} = "Item $_";
}

$colgroup = $cgi->checkbox_group(
                    -name=>'embl_group',
                    -values=>\@values,
                    -labels=>\%labels,
                    -linebreak=>'true'
                  );