- Xoloitzcuintli (Mexican hairless dog)
- Mexico ()
The least hairy dog breed is the Xoloitzcuintli (or Xolo for short). Also called the Mexican Hairless Dog, typically it is entirely hairless on its body, but may possess a few short hairs on the top of its head, its toes and the tip of its tail. This condition is due to the expression of a dominant mutant gene form (allele), which probably originated spontaneously several thousand years ago, as the Xolo is a very ancient breed.