Coat Patterns

All cats carry a tabby pattern, either striped (T-). The A-allele shows the tabby markings melanic pigment. Fills the entire hair and cats appear self or tortie. The A- allele shows the tabby markings.

Whether a cat is aa or A- has no effect on sex-linked red colors. The difference between selfs and tabbies in these colors is one of subtle polygenetic effects that determine whether the markings are faint or strong.

The inhibitor gene I blocks color production. In non-agouti cats only the roots are white, while in agouti cats, more of the hair shaft is affected. The difference between shaded selfs and silver tabbies is polygenic, affecting not only pattern but also depth of color.

Polygenic effects may also differentiate shaded from tipped coats, although some claim there is a "wide-band" inhibitor gene. In the sex-linked red colors, the differences between the smoke, shaded, silver tabby, and tipped cats are all polygenic.

Technically, all of these patterns are pointed. All are heat-sensitive with virtually all the color in the Siamese) or the very deepest color (in the Burmese) concentrated in the cooler extremities or points of the body.

Color is also slightly degraded or lightened for example, black becomes Seal in the Siamese arid Sable in the Burmese. The Tonkinese does not have its own gene: it is a softly pointed hybrid of pointed and sepia alleles. It always produces variants in these patterns, as well as its own mink pattern