$row{$origin} = {}; # set value to an empty hash reference 
$row{$origin}{$pip} = {};
$row{$origin}{$pip}{$probeset_id} = {};
$row{$origin}{$pip}{$probeset_id}{$affyscore} = {};
$row{$origin}{$pip}{$probeset_id}{$affyscore}{$gc} =$probeseq;