Hypoallergenic is the characteristic of provoking fewer allergic reactions in allergy sufferers.
Hypoallergenic means to have a decreased tendency to cause allergies; hypo means less, not none.
Hypoallergenic pets still produce allergens, but because of their coat type or absence of fur, typically produce less than others of the same species.
People with severe allergies and asthma might still be affected by a hypoallergenic pet.
For more information about the topic Hypoallergenic, read the full article at Wikipedia.org, or see the following related articles:
Hypoallergenic dog breeds — Hypoallergenic dog breeds are those touted as being hypoallergenic; that is, provoking fewer allergic reactions in allergy sufferers. These breeds usually shed less dander and hair and are, therefore, considered hypoallergenic.
However, even hairless dogs can produce enough dander to affect a highly allergic person.
http://www.sciencedaily.com/articles/h/hypoallergenic_dog_breeds.htm