quote:

Does not look all white to me.Looks brown.

quote:

Originally posted by Aspen Hill Adventures:
It might be leucistic.

From Wiki:

Leucism (occasionally spelled leukism) is a general term for the phenotype resulting from defects in pigment cell differentiation and/or migration from the neural crest to skin, hair or feathers during development. This results in either the entire surface (if all pigment cells fail to develop) or patches of body surface (if only a subset are defective) having a lack of cells capable of making pigment.

Since all pigment cell-types differentiate from the same multipotent precursor cell-type, leucism can cause the reduction in all types of pigment. This is in contrast to albinism, for which leucism is often mistaken. Albinism results in the reduction of melanin production only, though the melanocyte (or melanophore) is still present. Thus in species that have other pigment cell-types, for example xanthophores, albinos are not entirely white, but instead display a pale yellow colour.

More common than a complete absence of pigment cells is localized or incomplete hypopigmentation, resulting in irregular patches of white on an animal that otherwise has normal colouring and patterning. This partial leucism is known as a "pied" or "piebald" effect; and the ratio of white to normal-coloured skin can vary considerably not only between generations, but between different offspring from the same parents, and even between members of the same litter. This is notable in horses, cows, cats, dogs, the urban crow[1] and the ball python[2] but is also found in many other species.

A further difference between albinism and leucism is in eye colour. Due to the lack of melanin production in both the retinal pigmented epithelium (RPE) and iris, albinos typically have red eyes due to the underlying blood vessels showing through. In contrast, leucistic animals have normally coloured eyes. This is because the melanocytes of the RPE are not derived from the neural crest, instead an outpouching of the neural tube generates the optic cup which, in turn, forms the retina. As these cells are from an independent developmental origin, they are typically unaffected by the genetic cause of leucism.

Genes that, when mutated, can cause leucism include, c-kit,[3] mitf[4] and ednrb.[5]

quote:

Originally posted by Aspen Hill Adventures:
Sorry Olbiker, I didn't mean it to be confusing. I'm by far no expert in genetic terminology either, I am always studying as a poultry breeder (Chicken genetics really suck!). An easier way to visualize this: think of the word Phenotype to mean the way something looks as you see it. Loosely defined: If something is pink and you see that it is pink, that is the Genotype.

It may have plenty of genes (Genotype) that could make it look a variety of colors but what you actually see is the Phenotype.

Genotype, is of course, what genes something posesses. You don't always 'see' what the genes are but they can show up in later offspring.

So back to Phenotype and the way something looks...

Leucistic is sort of the opposite of melanistic. Some animals may look white or really light in color but still have normal colored eyes and skin. They are not albinos, which lack Melanin (normal skin pigments), which have visible pink skin and eyes.

Melanistic refers to overly dark pigmentation, like black squill, all black deer, etc.

Hope this helps explain: The pictured pronghorn seems lighter in color than normal, certainly not much white hair showing where most female antelope bear white patches. It might be odd, such as being leucistic, or, just might be totally normal and just has very little white hair. Maybe it is diseased, etc. No one will know for sure unless a close up look is taken.

So what can we say? Well, it is clearly NOT melanistic, NOT of normal phenotype (tan and white female) and is probably NOT albino.