Hairless dog

A hairless dog is a dog with a genetic disposition for hairlessness. There are two known types of genetic hairlessness, a dominant and a recessive type.

Dominant genes

Dogs with dominant genes for hairlessness can pass their attributes to their offspring in natural conditions, that is, not under the control of humans. Therefore, it is possible that, in some parts of the world, groups of hairless dogs came into existence without human intervention. Later in history, people developed these groups into a recognized breed.Worldwide recognized breeds at this time are the Chinese Crested Dog, the Mexican Hairless Dog, and the Peruvian Hairless Dog.The American Hairless Terrier is recognized only in some parts of north America.Other breeds there are said to exist are the Hairless Khala, African Hairless Dog (also known as the Abyssinian Sand Terrier, Egyptian Hairless Dog and Elephant Dog, the last being a reference to its grey skin) and the Thai Hairless Dog.

This type of genetic structure is said to be homozygous lethal for the dominant gene. This means that dogs with two dominant genes cannot live. Therefore, all dominant-hairless dogs have a heterozygous gene structure. There is also a homozygous recessive type, which is a coated variety.

For dogs where hairlessness is a dominant gene, hairless to hairless matings will on average produce 66.6% hairless and 33.3% coated puppies. For hairless to coated matings, there will be an average of 50%/50% coated to hairless ratio, while for coated to coated matings, all puppies will be coated [ [http://www.chinesecrested.no/en/articles/breeding/Genetics+part+II.+Defining+and+calculating+traits.html Genetics part II: Defining and calculating traits] ]

The Chinese Crested coated variety is called "Powder Puff", and is a recognized type. For the other breeds coated varieties are called "coated" and are not recognized as valid varieties for conformation showing.

References