The Chinese Crested Dog is a hairless breed of dog. Like most hairless dog breeds, the Chinese Crested Dog comes in three varieties, with hair, without hair and a combination of the two, which can be born in the same litter: the Powderpuff, the Hairless and the Hairy-Hairless. The Chinese Crested is considered a small breed, weighing on average 10–13 lb (4.5–5.9 kg). At first look, the Hairless and Powderpuff varieties of Chinese Crested Dogs appear to be two different breeds, but hairlessness is an incomplete dominant trait within a single breed. The Hairless has soft, humanlike skin, as well as tufts of hair on its paws ('socks') and tail ('plume') and long, flowing hair on its head ('crest'). In addition to being an incomplete dominant gene, the 'hairless' gene has a prenatal lethal effect when homozygous. Zygotes affected with double hairless genes never develop into puppies, and are reabsorbed in the womb. All Hairless Chinese Crested Dogs are therefore heterozygous. (Source: Wikipedia.org, CC BY-SA)