Events & Information
Great Dane Genetics
Base Color - Primary Coat Color
First, we'll look at the different loci that affect coat color in the Great Dane.
In each series, the possible alleles will be listed in terms of dominance, with the more dominant genes at the top, ranging to the most recessive at the bottom. The usual convention is to have the dominant gene capitalized, with recessive genes in lower case letters.
To begin, we'll touch on three series, the A-series, the E-series and the D-series. While all three do affect coat color in Great Danes, my intention here is to discuss primarily the Black, Harlequin, Mantle, Merle and White colors. All of these colors are AA, EE, and DD.
A-series: This determines the "base" color of the coat. Dogs have two forms of melanin in their coats. One, eumelanin, is dark. It varies in color due to variations in the protein that forms the framework of the pigment granule. The base form of eumelanin is black. Eumelanin can also be brown (also called chocolate or liver) or blue-gray. The other pigment, phaeomelanin, ranges from pale cream through shades of yellow, tan and red to mahogany.
E-series: The E-series is poorly understood and very controversial. In the simplest form, E=can produce eumelanin, and e=only phaeomelanin is produced (regardless of the A-series genes, and ee dog will show ONLY the yellow/red pigment, as is seen in yellow Labradors and Irish Setters.)
D-series: This determines whether the recessive gene that makes the eumelanin Blue instead of Black is present. There are only two alleles.
Other loci that affect coat color in dogs, but do not enter into discussion of the Great Dane are:
C albino series. All Great Danes are C, no albino traits. Other more recessuve alleles range from slight to full fading of color.
G graying The dominant G causes puppies that are born dark, with the color fading as they mature. All Great Danes are gg, no graying.
T ticking series. The dominant T produces individual pigmented hairs through spots of colored hair in otherwise white areas on the dog. All Great Danes are tt, no ticking.
B brown The recessive causes the eumelanin to be red/brown in color. The recessive b should not be present in Great Danes, although there is some chance that it is. The homozygous recessive bb produces red Doberman and chocolate Labradors. If present, it could produce chocolate Danes, "red merle" Danes, or a brown mask and/or stripes on Fawns and Brindles.
So, the Black, Harlequin, Merle, Mantle, and White Great Danes are ALL AAEEDDCCggttBB. To simplify discussion, we will ignore these genes in the rest of our discussion, as all loci are homozygous for a particular gene, these alleles will not vary from individual to individual.
Author: Ana Greavu-Rachow