Thanks for posting the information,thats one of the sites I found on the web.As for it being a huge problem,apparently among certain "show" circles it is.The breeder I spoke with tests all their dogs,but,some aren't testing positive until they're 3-4yrs.With some breeds this disorder may be sex-linked.After having 3 bad experiences with pure breds,I don't want to take any unnessary risks with another.