Editing Appaloosa (section)

== Color and spotting patterns ==

{{see also|Equine coat color}}
[[File:AppaloosaCharlie.jpg|thumb|left|Few spot leopard Appaloosa with wet coat, showing a "halo" effect of dark skin under the white coat, especially around spots.]]

The coat color of an Appaloosa is a combination of a base color with an overlaid spotting pattern. The base colors recognized by the Appaloosa Horse Club include [[bay (horse)|bay]], [[black (horse)|black]], [[chestnut (coat)|chestnut]], [[palomino]], [[Buckskin (horse)|buckskin]], [[cream gene|cremello or perlino]], [[roan (horse)|roan]], [[gray (horse)|gray]], [[Dun gene|dun]] and [[grullo|grulla]].<!--source uses "grulla" not "grullo"; same color --> Appaloosa markings have several pattern variations.<ref name="Identify" /> It is this unique group of spotting patterns, collectively called the "leopard complex",<ref name=APstudies/> that most people associate with the Appaloosa horse.<ref name="Identify">{{cite web|url= http://www.appaloosa.com/registration/indentify.htm |title= Guide to Identifying an Appaloosa |access-date=December 10, 2010 |publisher=Appaloosa Horse Club| archive-url= https://web.archive.org/web/20101211220821/http://appaloosa.com/registration/indentify.htm| archive-date= 11 December 2010 <!--DASHBot-->|url-status = live}}</ref> Spots overlay darker skin, and are often surrounded by a "halo", where the skin next to the spot is also dark but the overlying hair coat is white.{{sfn|Sponenberg, ''Equine Color Genetics''|p=92}}

It is not always easy to predict a grown Appaloosa's color at birth. Foals of any breed tend to be born with coats that darken when they shed their baby hair.<ref>{{cite web|url=http://imh.org/index.php/exhibits/online/horse-breeds-of-the-world/north-america/item/2233-appaloosa-horse |title=Appaloosa Horse |access-date=September 4, 2013 |work=International Museum of the Horse&nbsp;– Horse Breeds of the World |publisher=Kentucky Horse Park |url-status = dead|archive-url=https://web.archive.org/web/20130917235539/http://imh.org/index.php/exhibits/online/horse-breeds-of-the-world/north-america/item/2233-appaloosa-horse |archive-date=September 17, 2013 }}</ref> In addition, Appaloosa foals do not always show classic leopard complex characteristics.<ref name=APstudies/> Patterns sometimes change over the course of the horse's life although some, such as the blanket and leopard patterns, tend to be stable. Horses with the varnish roan and snowflake patterns are especially prone to show very little color pattern at birth, developing more visible spotting as they get older.{{sfn|Sponenberg, ''Equine Color Genetics''|p=92}}

The ApHC also recognizes the concept of a "solid" horse, which has a base color, "but no contrasting color in the form of an Appaloosa coat pattern". Solid horses can be registered if they have mottled skin, and one other leopard complex characteristic.<ref name="Identify" />

Solid Appaloosa horses are not to be confused with [[gray horse]]s, which display a similar mottling called "fleabitten gray". As they age, "fleabitten" grays may develop pigmented speckles in addition to a white coat. However, "fleabitten gray" is a different [[gene]], and is unrelated to the [[leopard complex]] gene seen in the Appaloosa breed. While the Appaloosa Horse Club (ApHC) allows gray Appaloosa horses to be registered, gray is rare in the breed.<ref>{{cite web |title=A Guide To Understanding Appaloosa Horse Coat Genetics |url=https://ihearthorses.com/whats-in-a-spot-appaloosa-coat-genetics/ |website=ihearthorses.com |date=5 June 2016 |access-date=29 June 2023}}</ref><ref>{{cite web |title=Flea Bitten Horse Color – Basic Grey Horse Colors Explained |url=https://www.besthorserider.com/flea-bitten-horse/?expand_article=1 |website=Best Horse Rider |access-date=29 June 2023}}</ref> Similarly, "dapple" gray horses are also different from Appaloosa horses, in terms of both coat color genes and patterning.<ref>{{cite web |title=What Is A Grey Dapple Horse? |url=https://www.besthorserider.com/grey-dapple-horse/ |website=Best Horse Rider |access-date=29 June 2023}}</ref>

Base colors are overlain by various spotting patterns, which are variable and often do not fit neatly into a specific category.<ref name="Identify" />  These patterns are described as follows:

{| class="wikitable plainrowheaders" style="width: 100%; clear: right;"
|-
! scope="col" | Pattern
! scope="col" | Description
! scope="col" | Image{{refn|Based on images from {{harvnb|Sponenberg, ''Equine Color Genetics''|pp=153–156}}.}}
|-
! scope="row" | Spots
| A horse that has white or dark spots over all or a portion of its body.<ref name="Identify" />
| [[File:Appaloosa (DSC00229).jpg|100px]]
|-
! scope="row" | Blanket or snowcap
| A solid white area normally over, but not limited to, the hip area with a contrasting base color.<ref name="Identify" />{{sfn|Sponenberg, ''Equine Color Genetics''|pp=90–91}}
| [[File:SnowflakeCrop.jpg|100px]]
|-
! scope="row" | Blanket with spots
| A white blanket which has dark spots within the white. The spots are usually the same color as the horse's base color.<ref name="Identify" />
| [[File:Appaloosa46-2.jpg|100px]]
|-
! scope="row" | Leopard
| A white horse with dark spots that flow out over the entire body. Considered an extension of a blanket to cover the whole body.{{sfn|Sponenberg, ''Equine Color Genetics''|pp=90–91}}
| [[File:Appaloosa stallion.JPG|100px]]
|-
! scope="row" | Few spot leopard
| A mostly white horse with a bit of color remaining around the flank, neck and head.{{sfn|Sponenberg, ''Equine Color Genetics''|pp=90–91}}
| [[File:Shiny fewspot.jpg|100px]]
|-
! scope="row" | Snowflake
| A horse with white spots, flecks, on a dark body. Typically the white spots increase in number and size as the horse ages.{{sfn|Sponenberg, ''Equine Color Genetics''|pp=90–91}}
| [[File:AppaloosaSnowflakes.jpg|100px]]
|-
! scope="row" style="white-space: nowrap;" | Appaloosa&nbsp;roan,&nbsp;marble <br /> &nbsp;&nbsp;or [[varnish roan]]
| A distinct version of the leopard complex. Intermixed dark and light hairs with lighter colored area on the forehead, jowls and frontal bones of the face, over the back, loin and hips. Darker areas may appear along the edges of the frontal bones of the face as well and also on the legs, stifle, above the eye, point of the hip and behind the elbow. The dark points over bony areas are called "varnish marks" and distinguish this pattern from a traditional [[roan (horse)|roan]].<ref name="Identify" />{{sfn|Sponenberg, ''Equine Color Genetics''|pp=90–91}}
| [[File:Flurrie 3.jpg|100px]]
|-
! scope="row" | Mottled
| A fewspot leopard that is completely white with only mottled skin showing.{{sfn|Sponenberg, ''Equine Color Genetics''|pp=90–91}}
| [[File:Appyfoal.jpg|100px]]
|-
! scope="row" | Roan blanket or Frost
| Horses with roaning over the croup and hips. The blanket normally occurs over, but is not limited to, the hip area.<ref name="Identify" />{{sfn|Sponenberg, ''Equine Color Genetics''|pp=90–91}}
| [[File:Standing Apaloosa.jpg|100px]]
|-
! scope="row" style="white-space: nowrap;" | Roan blanket with spots
| A horse with a roan blanket that has white and/or dark spots within the roan area.<ref name="Identify" />
| [[File:LeopardHorse.jpg|100px]]
|}

=== Color genetics ===

{{main|Leopard complex}}
{{see also|Equine coat color genetics}}
[[File:Stripedhooves.jpg|thumb|upright|Striped hooves are a characteristic trait.|alt=A brown and white striped horse hoof, with a dark colored leg partially visible]]

Any horse that shows Appaloosa core characteristics of coat pattern, mottled skin, striped hooves, and a visible white sclera, carries at least one [[allele]] of the dominant "leopard complex" (LP) [[gene]]. The use of the word "complex" is used to refer to the large group of visible patterns that may occur when LP is present.<ref name=APstudies>{{cite web|url=http://www.appaloosaproject.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=1&MMN_position=5:5 |author=Archer, Sheila |title=The Appaloosa Project: Studies Currently Underway |access-date=December 10, 2010 |publisher=The Appaloosa Project |url-status = dead|archive-url=https://web.archive.org/web/20110707152301/http://www.appaloosaproject.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=1&MMN_position=5%3A5 |archive-date=July 7, 2011 }}</ref> LP is an [[autosomal]] [[Dominance relationship#Incomplete and semi-dominance|incomplete dominant]] [[mutation]] in the [[TRPM1]] gene located at horse chromosome 1 (ECA 1).<ref name=Bellone2010/><ref name="Terry">{{cite journal |author=Terry, R. B. |author2=Archer, S. |author3=Brooks, S. |author4=Bernoco, D. |author5=Bailey, E. |year=2004 |title=Assignment of the appaloosa coat colour gene (LP) to equine chromosome 1 |journal=Animal Genetics |volume=35 |issue=2 |doi=10.1111/j.1365-2052.2004.01113.x |pages=134–137 |pmid=15025575}}</ref>  All horses with at least one copy of LP show leopard characteristics,<!--sometimes no spots, though--> and it is hypothesized that LP acts together with other patterning genes (PATN) that have not yet been identified to produce the different coat patterns.<ref name=APstudies/><ref>{{cite web|url= http://www.uky.edu/Ag/Horsemap/hgpcoatcolor.html |title= Applications of Genome Study&nbsp;– Coat Color |work=Horse Genome Project |publisher=University of Kentucky|access-date=July 3, 2008| archive-url= https://web.archive.org/web/20080724141007/http://www.uky.edu/Ag/Horsemap/hgpcoatcolor.html| archive-date= 24 July 2008 <!--DASHBot-->|url-status = live}}</ref> Horses that are [[heterozygous]] for LP tend to be darker than [[homozygous]] horses, but this is not consistent.{{sfn|Sponenberg, ''Equine Color Genetics''|p=93}}

Three [[single-nucleotide polymorphism]]s (SNPs) in the TRPM1 gene have been identified as closely associated with the LP mutation, although the mechanism by which the pattern is produced remains unclear.<ref name=APstudies/><ref name=Bellone2010/> A commercially available DNA based test is likely to be developed in the near future,<!--there's nothing that breeders can buy yet--> which breeders can use to determine if LP is present in horses that do not have visible Appaloosa characteristics.<ref name="APstudies" /><ref name=Bellone2010>{{cite journal|author=Bellone, R.|author2=Archer, S.|author3=Wade, C. M.|author4=Cuka-Lawson, C.|author5=Haase, B.|author6=Leeb, T.|author7=Forsyth, G.|author8=Sandmeyer, L.|author9= Grahn, B. |title=Association analysis of candidate SNPs in TRPM1 with leopard complex spotting (LP) and congenital stationary night blindness (CSNB) in horses|journal= Animal Genetics |volume=41|issue= Supplement s2| page=207| date=December 2010|doi= 10.1111/j.1365-2052.2010.02119.x|s2cid=84404747 }}</ref>

Not every Appaloosa exhibits visible coat spotting, but even apparently solid-colored horses that carry at least one dominant LP allele will exhibit characteristics such as vertically striped hooves, white [[sclera]] of the eye, and mottled skin around the eyes, lips, and genitalia.<ref>{{cite web|url= http://www.vgl.ucdavis.edu/services/coatcolor.php |title= Introduction to Coat Color Genetics |access-date=January 31, 2008 |publisher= Veterinary Genetics Laboratory, School of Veterinary Medicine, University of California-Davis| archive-url= https://web.archive.org/web/20080120014506/http://www.vgl.ucdavis.edu/services/coatcolor.php| archive-date= 20 January 2008 <!--DASHBot-->|url-status = live}}</ref>  Appaloosas may also exhibit [[sabino horse|sabino]] or [[pinto horse|pinto]] type markings; as pinto genes may cover or obscure Appaloosa patterns, pinto breeding is discouraged by the ApHC, which will deny registration to horses with excessive white markings.<ref name=Rule205>{{cite web|url= http://www.appaloosa.com/registration/handbook.htm|title= 2012 Appaloosa Horse Club Handbook|access-date= April 2, 2012|publisher= Appaloosa Horse Club|format= PDF|pages= Rule 205.C|archive-date= April 22, 2011|archive-url= https://web.archive.org/web/20110422185434/http://appaloosa.com/registration/handbook.htm|url-status= dead}}</ref> The genes that create these different patterns can be present in the same horse. The Appaloosa Project, a genetic study group, researchers the interactions of Appaloosa and pinto genes, and how they affect each other.<ref>{{cite web|url= http://www.appaloosaproject.info/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=1&MMN_position=5:5|title= What is the Appaloosa Project?|access-date= October 25, 2009|publisher= The Appaloosa Project|archive-url= https://web.archive.org/web/20080824213835/http://www.appaloosaproject.info/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=1&MMN_position=5:5|archive-date= August 24, 2008|url-status= dead}}</ref>