Dilution gene is a popular term for any one of a number of gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

s that act to create a lighter coat color in living creatures. There are many examples of such genes:

General

Diluted coat colors have melanocyte

Melanocyte

-External links: - "Eye: fovea, RPE" - "Integument: pigmented skin"...

s, but vary from darker colors due to the concentration or type of these pigment-producing cells, not their absence. Pigment dilution, sometimes referred to as hypomelanism, has been called leucism, albinism (perfect, impartial, or dilute), ghosting, paling, and isabellinism.

• Albinism
  Albinism
  Albinism is a congenital disorder characterized by the complete or partial absence of pigment in the skin, hair and eyes due to absence or defect of an enzyme involved in the production of melanin...
  
   describes a condition where there is no color pigment
• Leucism describes a condition that creates loss of pigment cells

Horses

• Equine coat color genetics
  Equine coat color genetics
  Equine coat color genetics determine a horse's coat color. There are many different coat colors possible, but all colors are produced by the action of only a few different genes. The simplest genetic default color of all domesticated horses can be described as either "red" or "non-red", depending...
  
   discusses color genes in horse
  Horse
  The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...
  
  s, including a brief description of dilution genes
• Equine coat color
  Equine coat color
  Horses exhibit a diverse array of coat colors and distinctive markings. A specialized vocabulary has evolved to describe them.While most horses remain the same color throughout life, a few, over the course of several years, will develop a different coat color from that with which they were born...
  
   describes various colors in horses
• Cream gene
  Cream gene
  The cream gene is responsible for a number of horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut will become palomino if they are heterozygous, having one copy of the cream gene, or cremello, if they are homozygous. Similarly, horses with a bay...
  
  , describes the process for horses by which the cremello, perlino, smoky cream double-dilute colors are created as well as the buckskin, palomino
  Palomino
  Palomino is a coat color in horses, consisting of a gold coat and white mane and tail. Genetically, the palomino color is created by a single allele of a dilution gene called the cream gene working on a "red" base coat...
  
   and smoky black single dilute colors.
• Dun gene
  Dun gene
  The dun gene is a dilution gene that affects both red and black pigments in the coat color of a horse. The dun gene has the ability to affect the appearance of all black, bay, or chestnut -based horses to some degree by lightening the base body coat and suppressing the underlying base color to the...
  
   describes another common dilution gene in horses
• Champagne gene
  Champagne gene
  The champagne gene is a simple dominant allele responsible for a number of rare horse coat colors. The most distinctive traits of horses with the champagne gene are the hazel eyes and pinkish, freckled skin, which are bright blue and bright pink at birth, respectively...
  
  , describes a different and rarer dilution gene in horses that also creates cream coloring, pale skin with mottling and light-colored eyes.
• Pearl gene
  Pearl gene
  The Pearl gene, also known as the "Barlink factor," is a dilution gene that somewhat resembles the cream gene and the champagne gene, but is neither. It is a somewhat rare dilution gene found in the American Quarter Horse, American Paint Horse, and Peruvian Paso. The same mutation appears in...
  
  , also called the "Barlink factor," is a recessive gene. One copy of the allele has no effect on the coat color of black, bay or chestnut horses. Two copies on a chestnut horse produce a pale, uniform apricot color of body hair, mane and tail as well as pale skin. It also interacts with Cream dilution to produce "pseudo-double" Cream dilutes with pale skin and blue or green eyes.
• Silver dapple gene
  Silver dapple gene
  The silver dapple gene is a dilution gene that affects the black base coat color. It will typically dilute a black mane and tail to flaxen, and a black body to a shade of brown or chocolate. It is responsible for a group of coat colors in horses called "silver dapple" in the west, or "taffy" in...
  
  , describes a dilution gene that works in a unique manner, lighting the mane and tail of a horse to a greater degree than the body color (opposite of most dilution genes, which act more strongly on the body color)
• White (horse)
  White (horse)
  White horses are born white and stay white throughout their life. White horses may have brown, blue, or hazel eyes. "True white" horses, especially those that carry one of the dominant white genes, are rare...
  
   describes several unique genetic processes that create truly white, not diluted, color in horses.
• Gray (horse)
  Gray (horse)
  Gray or grey is a coat color of horses characterized by progressive silvering of the colored hairs of the coat. Most gray horses have black skin and dark eyes; unlike many depigmentation genes, gray does not affect skin or eye color Their adult hair coat is white, dappled, or white intermingled...
  
   explains the process of the gray gene, which lightens the coat over time, but is not a dilution gene.

See also

• wikispecies:Felis sylvestris catus (cat)
• wikispecies:Equus caballus (horse)