Uncommonly, a prize-winning pedigreed show cat can be worth thousands of dollars but most are loved pets.
Some breeders take great care to select for the healthiest animals, and this has the potential to reduce the incidence of health issues.
This population structure is addressed in Patterns of molecular genetic variation among cat breeds.
The entire Cornish Rex breed can be traced back to a single parent animal with an unusual genetic mutation producing a curly coat.
Both the Burmese and Tonkinese breeds can be traced back to a single cat, Wong Mau, which was brought from Burma in the 1930s.
This genetic shifting is most obvious in the two oldest, most popular and most distinctive breeds of show cat - the Persian and the Siamese.