Definition of Terms
polygene (n.)  Any of a group of nonallelic genes, each having a small quantitative effect, that together produce a wide range of phenotypic variation. Also called multiple factor, quantitative gene

Introduction
The genetics of the American Ringtail are still technically a working hypothesis. Although litter data to date has supported this hypothesis, it will take much more data to make it a certainty. This definition of the genetics is therefore subject to revision and refinement as time goes on.

What are we working with?
 The unique tail set of the American Ringtail is a polygenic trait consisting of (at least) two genes. One is a dominant thought to be sex linked (carried in the X chromosome), and the other a simple recessive.

Dominant Aerial Tail
The dominant element of the American Ringtail genetics that appears to be sex linked produces what is called the "aerial" tail, or a tail that is held up and over the back but not curled back on itself. This trait has been seen in many breeds and domestic populations. (See Other Ringtails).

Recessive Tail Curl
The recessive gene produces a tail that curls back on itself. It is independent of the dominant. This is the element that has been seen far more rarely in randomly bred cats around the world, but is more common in the domestic and feral populations around Hayward, CA, where the original American Ringtail came from.

Right: This female cat is a feral cat in the same location that Solomon, the first American Ringtail was found. Her tail does not lie flat on her back, but it does curl. This could be an example of a cat with only the recessive curl genetics and not the dominant aerial tail. THis is by far the rarest expression seen in ring tailed cats.

Breeding a full American Ringtail
The combination of the dominant aerial tail and recessive tail curl yields a perfect American Ringtail. This kitten is an early onset American Ringtail female at about 5 weeks of age. It takes at least two gerations to produce a full American Ringtial from an outcross, and can take up to four.

There are several factors that point towards the aerial tail gene being sex linked.

• Fully expressed (early onset) Ringtail females have only been born to two parents with the dominant gene( both parents also carrying or expressing the recessive).
• The percentage of females expressing the dominant to boys looking the same is similar to that of solid red girls to solid red boys (red is a sex linked dominant gene).
• Females born to outcross parents often display partial aerial tail traits (see Georgia of Singaling), leading us to believe that they have only one copy of the dominant rather than the two that are required for full expression. This would be similar to a tortie; the two dominant genes attached to the X share the expression.

Far more test breedings are needed to evaluate litters born to females carrying the recessive but not expressing the dominant bred to full Ringtailed boys. If these litters ever produce an early onset female Ringtail, then the dominant is not strictly attached to the X Chromosome.