All highlands originated as either black or red.
Over time, these colors have become *diluted*. The result of this dilution is two distinct color charts… one is the result of varying dilutions of black and the other is variations of dilutions of red.
They look like this :
Black > Dun > Silver
Or
Red > Yellow > White
All highland colors are described with a dual gene set as every animal inherits a color gene from each parent.
No Dilution
Black = N/N
Red = N/N
Partial dilution
Dun = Dh/N
Yellow = Dh/N
Complete dilution
Silver = Dh/Dh
White = Dh/Dh
You’ll notice that they look identical, not because of their color but rather because of the amount of dilution.
There are separate genes that influence the actual color and those are called Alleles.
There are three primary Alleles.
ED = black influence
e = red influence
E+ = wild type which is something of a brownish red color influence.
Alleles are also donated from each parent so there are two for every cow.
ED/ED = very dominate black concentration
e/e = very red
E+/E+ = may create a modeling of the base color with a dark brown referred to as brindle.
These can be mixed and matched but ED or black is always dominate.
ED/e = mainly black influence
ED/E+ = mainly black influence
This doesn’t mean that the cow will be black, it just means that whatever amount of dilution it is, it will be on the black color spectrum … so black, dun or silver.
e/E+ = red influence combined with wild type will mean that your cow is on the red color spectrum … so red, yellow or white, depending on the amount of dilution.
E+/E+ isn’t directly linked to the color spectrum but it may create that brindle effect on whatever the animals color is.
So now if I have only a DNA color test result of N/N ED/ED I know that this a truly black cow. There is no dilution and both alleles are dominate black.
N/N ED/e is still a black cow because the N means no dilution and we know that ED or black is the dominate color influence and not red or e.
N/N e/e is a red cow because there is no dilution and no black influence
N/N E+/E+ we would have no idea what color this cow is without seeing it but it may have a brindle or brown modeling pattern to it’s coat.
Dh/N ED/ED is a dun cow. The Dh means that one of the parents of this animal donated a dilution gene. The ED/ED means that the partial diluted color was heavily influence by black. One dilution of black influence equals dun.
Dh/N e/e is a yellow cow. One dilution with no black influence equals yellow.
Dh/N E+/E+ is either a dun or yellow; possibly brindle marked cow.
Full dilutions
Dh/Dh ED/ED = silver
Dh/Dh e/e = white
The exception on fully dilute animals is with brindles.
Dh/Dh E+/E+ is a not a brindle as these full dilution colors can’t represent the necessary pigmented modeling. They are absent of pigment.
There are other common exceptions to DNA color results when crossing highlands with other breeds. The white park, for example has a dominate color expression that resembles that of a white coat that blankets the cow.. all but it’s ears. The cows DNA results will still look the same as their solid highland counterpart but only the ears will reflect the cows highland color.
So a white cow with brown tips would have one dilution (Dh/N). The allele influence would be the same for the solid colored highland, so it would have some amount of black influence to be dun, either ED/ED or ED/e or ED/E+.
The Galloway is another exception… it leaves a white band around the center of the highland cross but the rest of its color is still highland as is it’s DNA results.
If you know this information for all of your breeding stock, you can make informed projections about the color outcomes of your calves. While it’s rarely 100% accurate, it’s a pretty good indicator to help you plan. It obviously helps to know what animals to breed in order to get the colors you want. Ask the breeders to provide this information to you on your calves and I will help you with this when you are selecting your bull if you’d like.
