Defining Breed Differences IN 3D

We cat aficionados know about the fabulous variety of cat breeds—just compare a Siamese to a Persian, or a Singapura to a Maine Coon. But to most of the world—and I’m sorry to mention the D-word in CatTalk—it is dogs that are the kings of diversity; cats are thought to all be much the same, except for superficial differences in coat color and length. The great variety of dogs is backed up by scientific research showing that the variation in head shape among dog breeds far outstrips the differences among wild canid species, such as wolves and foxes.

- Johnathan Losos and Duncan Irschick

No comparable study has been conducted on cats, however. A colleague of mine, Duncan Irschick, who is a professor at the University of Massachusetts, Amherst, and I decided to remedy this situation. Specifically, our plan was to precisely determine the variability in cat heads to compare to the variation seen among dog breeds and wild species of felines like lions, tigers, and ocelots.

The research is not just about bragging rights. Now that the housecat genome has been sequenced, it will soon be possible to discover the genes responsible for differences among breeds. But to do such studies, exact measurements of anatomy are required. Qualitative terms like “wedge” and “egg-shaped” are fine for breed standards, but more precision is needed to detect the relationships between genes and anatomical variation. In turn, quantifying the discovery of such genetic associations will also benefit the detection and treatment of feline medical problems.