I am afraid I have to agree with what has already been said. I owned and exhibited G.S.Ds many years ago. The colour is less important to me, I quite like the whites (though they are not shown) and know they have a good following and there are some dedicated breeders out there breeding whites but they do health check. No one is just getting at you for no reason it is out of genuine concern for the dogs themselves. Why not just have the health checks done and then offer your dog up for stud if the results are ok and also give yourself peace of mind.