EquiGenetic Relevations
Splash White 1 (Helmscheckung)
Splash White, also known as Helmscheckung, is a genetic variation in horses that produces a unique and striking coat pattern. This autosomal semi-dominant pattern occurs in many different breeds. So far, 11 Splash White mutations have been discovered, one of which, Macchiato, has been removed as it is expected to become extinct. Thus, 10 mutations remain recognized, with Splash White 1 being the most common variant. This mutation is found in many warmblood breeds such as Trakehners, Holsteiners, Hanoverians, and KWPN, as well as Welsh Ponies, Gotland Ponies, Shetland Ponies, Icelandic Horses, and Quarter and Paint Horses.
Genetic Code:
The genetic code for Splash White is as follows:
- N/N = no Splash present
- N/SW1 = heterozygous Splash present
- SW1/SW1 = homozygous Splash present
N/N Genotype: Horses with the N/N genotype do not have the Splash pattern and cannot pass this Splash variant to their offspring.
N/SW1 Genotype: Horses with the N/SW1 genotype have the classic Splash pattern. They have a 50% chance of passing this Splash variant to their offspring. Crossings with an N/N genotype have a 50% chance of producing a Splash foal.
SW1/SW1 Genotype: Horses with the SW1/SW1 genotype have the classic Splash pattern in full expression. They will pass this Splash variant to all their offspring. Crossings with any genotype will exclusively produce Splash offspring.
Phenotypic Characteristics of Splash White
Heterozygous Horses: These horses can have a very minimal expression of the pattern, ranging from no white hairs at all (appearing as a solid-colored horse) to blue eyes and a blaze, along with high white legs, belly spots, and a two-toned tail. Typically, Splash White is accompanied by a wide blaze and leg markings.
Homozygous Horses: These horses look as if they have been dipped in white paint from the bottom up. They can be predominantly white, and blue eyes are absolutely typical.
Combinations and Risks
Combination with other Patterns: Splash White can be combined with other patterns. For example, a combination with Tobiano often results in a lot of white, and sometimes even completely white horses that are genetically patterned. In combination with White Spotting 20, a horse with Splash can be “boosted” by W20, resulting in an extremely high amount of white.
Health Risks: As with other patterns, the Splash gene can be associated with deafness. Homozygous Splash White horses are particularly at risk. The cause is the absence of melanocytes in the inner ear. Therefore, some breeders classify Splash as a defect breed.
Genetic Localization
The genetic basis of Splash White 1 is located on the KIT locus.
Splash is considered the pattern of blue eyes. Blue eyes are a main characteristic of Splash, but not all horses with blue eyes automatically have Splash. However, blue eyes are a good indicator.
Here you can clearly see that heterozygous Splash can be very minimal. This Shetland pony stallion has no white markings except for 3-4 hairs on his forehead and also has blue eyes.
Another indicator of Splash is irregular blazes or blazes that start narrow at the top and become wider towards the bottom, as seen here.
Another indicator of Splash is irregular blazes or blazes that start narrow at the top and become wider towards the bottom, as seen here.
Most commonly, Splash is associated with broad blazes and blue eyes.
Most commonly, Splash is associated with broad blazes and blue eyes.
This stallion is heterozygous Splash White 1 and exhibits a typical broad blaze, blue eyes, a belly spot, high white legs, and a two-toned tail, which occasionally occurs in heterozygous and very often in homozygous Splash horses.
