Yes, the American Hairless Terrier is considered a hypoallergenic breed—however, this does not mean allergic individuals will never have a reaction to an AHT. Allergic reactions are triggered by more than just fur. Dander and saliva contribute to allergies as well. Because any dog can trigger an allergic reaction in a human, there is no guarantee—but many claim the American Hairless Terrier is one of the best choices for allergy sufferers.
An American Hairless Terrier may produce moisture along the spine in hot weather or while under stress, but whether this is sweat is unclear. All dogs are covered with hair follicle-associated glands that produce pheromones. Dogs don't sweat from these glands; they sweat only from their paw pads and noses—areas where there is a second type of gland, but no hair. Because the American Hairless Terrier does not have hair, he may sweat—but the claim has not been scientifically proven.
Is the American Hairless Terrier Actually Hairless? American Hairless Terriers are born with light, downy hair that begins to fall out by a few weeks of age. They are completely hairless by eight weeks of age, or may retain an incredibly fine type of hair called vellus—this hair is similar to 'peach fuzz' on humans. The American Hairless Terrier also comes in a coated variety.
As a new breed, the American Hairless Terrier has a tiny gene pool with little genetic diversity. The hairless gene in the AHT is a recessive gene, meaning both parents need to pass the gene in order to always produce hairless puppies. In order for this to be possible, there would be a high instance of inbreeding while developing the Hairless Terrier without allowing coated dogs in the gene pool. Coated Hairless Terriers bred to hairless AHTs may produce coated puppies, but those coated puppies will also carry the hairless gene. This coated dog may go on to produce hairless puppies, thus expanding the gene pool. Though allowed, breeding coated to coated AHTs is discouraged as it doesn't work toward the goal of a hairless breed. Coated AHTs are currently allowed under the breed standard in order to maintain the health of the breed—but the goal is to eventually phase out the coated variety when there is enough genetic diversity to prevent serious health concerns within the breed.