http://well.blogs.nytimes.com/2011/0...ergy-free-dog/
There is no such thing as alergy free dog (I'm a biologist; immunologist to be more precise - and allergies are immunological reactions of your organism). The allergens (a special kind of protein) are in the skin and the saliva. Allergy free species may be produced only in laboratory (I think in Japan there were some allergy free cats breeded once), couse you have to change the DNA of the animal to get rid of this special protein from the organism (I will not go into details).
Humans also very often get used to the allergens around them and it may happened that you will not be allergic on your own dog, but have simptoms with any other dog you will meet.
Allergy free cat/dog breeds are a myth.