Genetics • The Broken Pattern
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The genetic code for each color variety will be the same as listed for that recognized color with the following difference: ??????En???
Breeding Better
words: Donelle Bomben & Sandra Wight photos: Brian Caudill, 3 Bears Rabbitry & Sandra Wight
Brokens The Broken Jersey Wooly, presented by Brian Hartzell, was accepted by the ARBA as a recognized variety in 2004 and has become a popular addition to the breed, competing regularly for top honors. Though the majority of this article was written for the Netherland Dwarf and appears in the Dwarf Guidebook, genetics are the same across all breeds.
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he broken pattern found in rabbits is the result of the [Enen] series of genes. Generally it works in a very simple manner, with the [EnEn] combination resulting in too much white, thus producing what is commonly called a “Charlie”. The [Enen] combination results in a broken pattern on the coat with the pattern placement being controlled by various sets of modifying genes. The pattern can range from too much color to not enough color. The [en en] recessive pairing always results in a “solid” or normally colored rabbit dependent upon the other genes for coat color and coat pattern that the animal carries. These may be any of the normal “patterns” such as agouti, shaded or self. The broken pattern genes produce the so-called “blanket” pattern as is commonly found in the Holland Lop and the Mini Lop breeds. However, the same set of genes is also responsible for the “English Spot” pattern as is found in both the English Spot and Checkered Giant breeds. In this second pattern (usually referred to as “spotted” rather than “broken” by most breeders), there is more white found on the coat and the color is supposed to be found in a more or less very specific pattern or location. The usual pattern is a mostly white background with color located as a “moustache” or butterfly on the nose, full eye circles, both ears fully colored, a spine stripe, and a specific pattern of spotting on the main body area.
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The broken color genes [En] are thus responsible for producing both the blanket pattern and the spotted pattern. It is the modifying genes that are present in an animal that determine which pattern is produced on each individual rabbit. An [enen] pair will always produce a normally colored (nonbroken) rabbit and the [EnEn] will always result in a “Charlie” with a mostly white coat. The [Enen] will, of course, have a broken coat pattern of some sort, the pattern being controlled by
Breeding Tips for Better Brokens • Breeding Broken to Broken will produce Broken, Charlie & solid. Broken is a dominant-recessive gene combination. Each Broken parent can send a ‘solid’ gene to an offspring, producing a solid. Or each parent can send a Broken gene to a kit & produce a Charlie. • Charlies are Brokens that are very lightly marked, and often have a ring around the eye. Using Charlies to produce Brokens can be difficult. (see picture of Charlies above. • Heavily cull rabbits that have scattered white hairs in the colored section of the coat. • While any spot in the whisker bed and/or nose is acceptable, an evenly balanced nose marking is preferred. • Breeders are discouraged from using a non-broken Wooly with a white toenail or spot in their Broken program, as resulting solid colored offspring may carry nail or spotting faults into future generations.
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