Equine Genes

Agouti (A)

The agouti signaling protein gene (often shortened to agouti or ASIP) controls where black pigment is produced on the horse.

Ancestry & Composition Panel*

Androgen Insensitivity (ais) *

Androgen Insensitivity Syndrome (AIS), previously known as Testicular Feminization Syndrome, is a disorder of sexual development in which a horse with a XY SRY+ karyotype appears female.

Anhidrosis (ANH) NEW!

Black/Red (E/e)

The black/red factor test (also known as “extension”) determines the underlying base color of a horse in the absence of any modifiers (such as agouti).

Brindle/IP

Incontinentia pigmenti (IP) is a variant of the IKBKG gene on the X chromosome, causing in weepy skin lesions present at birth.

Cerebellar Abiotrophy (ca)

Cerebellar Abiotrophy (CA) is a degenerative neurological disorder due to the death of large neurons (Purkinje cells) in the cerebellum.

Champagne (CH)

Champagne is a variant of SLC36A1 that reduces the amount of both black and red pigments.

Cream (CR)

Cream (CR, sometimes seen as “Crème”) and pearl (prl, sometimes called “apricot” or “Barlink factor”) are variants of the SLC45A2/MATP gene that reduce the overall amount of pigmentation, thus diluting the color of the horse.

Curly Coat (KRT25) "CU1", (SP6) "CU2"

Dominant White 1No21 (W1No21)

Dominant white (“W”) refers to a class of white spotting patterns in which a horse with one copy generally displays markings on 50-100% of the body.

Dun (D)

Dun, a dominant dilution gene, is the ancestral coat colour of equids.

Dwarfism (Friesian and acan)

Dwarfism is characterized by abnormal growth, leading to either a disproportionate body type or overall smaller body size.

Equine Metabolic Syndrome (EMS)

Equine Metabolic Syndrome (EMS) is a wide-spread issue in the horse population.

Equine Recurrent Uveitis (ERU)

Equine Recurrent Uveitis (ERU) is the most common cause of blindness in horses.

Foal Immunodeficiency Syndrome (fis)

Foal immunodeficiency syndrome (FIS) is a failure in the development of the adaptive immune system.

Fragile Foal Syndrome (ffs or wffs)

Warmblood fragile foal syndrome is a connective tissue disorder resulting in joint laxity and extremely thin skin that is only loosely connected to the body.

Frame/Lethal White Overo (LWO)

Lethal white overo (also known as frame overo) is a variant of the EDNRB gene that produces a white spotting pattern.

Gaited (DMRT3)

Horses display a wide variation in locomotion, with “gaited” breeds displaying a range of unique footfall patterns at intermediate speeds.

Glycogen Branching Enzyme (gbed)

Glycogen branching enzyme deficiency is a lethal recessive disorder characterized by seizures, muscle weakness, respiratory failure, and death.

Grey (G)

Grey is a modifier of coat colour, resulting in a progressive loss of pigmentation throughout the coat.

Height Prediction (LCORL) "H1"

The domestic horse displays a wide range of size variation, from the tiny Miniature Horses to the towering draft breeds.

Hereditary Equine Regional Dermal Asthenia (herda)

Hereditary equine regional dermal asthenia (HERDA) is a degenerative skin disease that primarily affects the American Quarter Horse breed.

Hoof Wall Separation Disease (hwsd)

Hoof wall separation disease is characterized by separation and breakage of the dorsal hoof wall extending up from the sole.

Hydrocephalus (hyd)

Hydrocephalus is an abnormal build up of cerebral spinal fluid around the brain. In the Friesian, it is believed that a narrowing of a passage within the brain prevents normal fluid absorption, leading to an obvious external cranial distension.

Hyperkalemic Periodic Paralysis (HYPP)

Hyperkalemic Periodic Paralysis (HYPP) is a dominant genetic disorder resulting from defects in sodium channels in the muscle.

ImmuneNoMediated Myositis (IMM)

Immune-mediated myositis (IMM) is an autoimmune disease which, when triggered by an infection, or certain vaccinations (i.e. influenza) can cause severe muscle loss (atrophy) within a period of 3 days (up to 40% in 72 hours).

Impaired Acrosomal Reaction (iar) *

In normal fertilization, the the head of a sperm binds to the egg and releases the contents of a structure known as the acrosome.

Junctional Epidermolysis Bullosa (jeb1)

Junctional epidermolysis bullosa (JEB), also known as red foot disease or hairless foal syndrome, results in the inability to produce the proteins needed to keep the skin on the body.

Junctional Epidermolysis Bullosa (jeb2)

Kissing Spines Susceptibility (KSS)

Laminitis Risk (LAM)

Lavender Foal Syndrome (lfs)

Lavender foal syndrome (LFS), also known as coat color dilution lethal, is a neurological dysfunction in newborn foals.

Leopard Spotting Complex (LP)

Leopard Complex Spotting (LP), also known as Appaloosa spotting, is a variant of the TRPM1 gene that results in a collect of unique pigmentation patterns.

Lethal White Overo (LWO)

Lordosis (Swayback)

Lordosis, also known as swayback, is a curvature or dip in the spine that is often seen in older horses.

Malignant Hyperthermia (MH)

Malignant hyperthermia (MH) is a muscle disorder in which anaesthesia, stress, or extreme exercise trigger a hypothermic state.

Mushroom Dilution (mu)

Myostatin (Sprint vs. Endurance)

Thoroughbred races are held at a variety of distances, with individual racehorses usually displaying a preference for a range.

Myotonia (MY)

Myotonia is a rare disorder involving a slowed relaxation of muscles after contraction.

Pattern 1 (PATN1)

Leopard Complex Spotting (LP), also known as Appaloosa spotting, is a variant of the TRPM1 gene that results in a collect of unique pigmentation patterns.

Pearl (prl)

Polysaccharide Storage Myopathy (PSSM1)

Polysaccharide Storage Myopathy (PSSM) is a glycogen storage disorder in which affected horses have chronic episodes of exertional rhabdomyolysis (“tying-up”).

Recurrent Laryngeal Neuropathy (RLN) Roaring

Sabino 1 (SB1)

Sabino 1 is a variant of the KIT gene that causes the sabino (or sabino overo) spotting pattern.

Severe Combined Immunodeficiency (scid)

Severe combined immunodeficiency disease is a condition in which the foal has essentially no immune system, due to a complete absence of certain types of immune cells, specifically B and T lymphocytes.

Silver (Z)

Silver (sometimes called silver dapple or taffy) is a variant of PMEL17 that dilutes black pigment.

Snowdrop (sno)

Splashed Whites 1No4 (SW1No4)

Splashed white overo is a white spotting pattern characterized by extended white markings on the legs, face, and often tail/belly, sometimes described as a horse that was dipped in paint.

Squamous Cell Carcinoma Risk (SCC)

Squamous Cell Carcinoma is the most common cause of eye cancer in horses. It is also responsible for a large percentage of tumors throughout other parts of the equine body.

Sunshine (sun)

Temperament (Curiosity vs. Vigilance) *

Tiger Eye (te)

Tobiano (TO)

Tobiano is a large inversion of equine chromosome 3 (ECA3) that likely disrupts the regulation of the KIT gene.

West Nile Virus Risk (WNVR)*

West Nile virus is a mosquito-borne virus that can infect multiple types of mammals, including horses.

nd1/nd2 (nonNodun Primitive Markings)