L E O P A R D C O M P L E X
The patterning many people attribute to Appaloosas (but can be found in some other breeds) is polygenic, meaning that there are multiple genes that contribute to the expression of a particular pattern. The two known genes that are involved in these patterns are leopard complex (LP) and pattern-1 (PATN1).
The leopard complex gene is an incomplete dominant. It functions to allow coat depigmentation and Appaloosa characteristics such as skin mottling, hoof striping, and a white sclera. Without a pattern gene, a dominant LP horse will be snowflake or varnish. With a pattern gene, white patterning can express on the coat. When heterozygous, the leopard complex gene allows colored spotting within the white pattern. When homozygous, fewer to no colored spots are allowed within the white pattern.
The known pattern gene contributes to leopard-type patterning including leopard and few-spot. A horse with dominant PATN1, but no dominant leopard complex will be solid with no Appaloosa characteristics. A heterozygous leopard complex horse with dominant PATN1 will likely be a near-leopard or leopard. A homozygous leopard complex horse with dominant PATN1 will likely be a few-spot or fully white in color.
Other patterns such as spotted blanket and snowcaps cannot be definitively attributed to the PATN1 gene. Research of pedigrees and patterns has indicated that these particular patterns are possibly polygenic as well, with multiple factors on top of leopard complex and/or pattern-1.
The leopard complex gene is an incomplete dominant. It functions to allow coat depigmentation and Appaloosa characteristics such as skin mottling, hoof striping, and a white sclera. Without a pattern gene, a dominant LP horse will be snowflake or varnish. With a pattern gene, white patterning can express on the coat. When heterozygous, the leopard complex gene allows colored spotting within the white pattern. When homozygous, fewer to no colored spots are allowed within the white pattern.
The known pattern gene contributes to leopard-type patterning including leopard and few-spot. A horse with dominant PATN1, but no dominant leopard complex will be solid with no Appaloosa characteristics. A heterozygous leopard complex horse with dominant PATN1 will likely be a near-leopard or leopard. A homozygous leopard complex horse with dominant PATN1 will likely be a few-spot or fully white in color.
Other patterns such as spotted blanket and snowcaps cannot be definitively attributed to the PATN1 gene. Research of pedigrees and patterns has indicated that these particular patterns are possibly polygenic as well, with multiple factors on top of leopard complex and/or pattern-1.
LP_ nn or LPlp PATN1_ or LPLP PATN1_