Why spay/neuter both parents? Just don't breed them together again? Or do a DNA test on them to find out which one has the gene?
I know you don't know the answers and they aren't your dogs. My insane curiosity makes me ask these things!
Seger vom Sitz von der Hose
Forever loved and missed.....Banshee
~The strength of one's opinion should not exceed their knowledge on the matter~