| Color Genetics in Dobermans |
Coat color inheritance in the Doberman is relatively easy to predict. While there are actually 5 colors,
there are only 3 sets of genes that determine color. Basic scientific nomenclature dictates that a capital
letter is used to represent the dominant gene in a pair, and the lower case letter designates the
recessive.
there are only 3 sets of genes that determine color. Basic scientific nomenclature dictates that a capital
letter is used to represent the dominant gene in a pair, and the lower case letter designates the
recessive.
The first pair of genes we will discuss are the 2 most common, seen in all Dobes. They are the color genes,
determining the basic, intrinsic color of the Dobe, either Black (B) or red (b). All Dobermans are either
black or red, but color can be modified by the other 2 pairs of genes. If a Doberman has 2 Black genes
(BB) it will be black. If it has 2 red genes (bb) it will be red. If it has one of each (Bb), it will be a
red-factored black, which is a black capable of producing red. Every parent Doberman contributes either
a black gene or a red gene to it?s offspring. BB animals always contribute a B gene, bb animals always
contribute a b gene, and Bb animals contribute one or the other, with a 50% probability of each.
determining the basic, intrinsic color of the Dobe, either Black (B) or red (b). All Dobermans are either
black or red, but color can be modified by the other 2 pairs of genes. If a Doberman has 2 Black genes
(BB) it will be black. If it has 2 red genes (bb) it will be red. If it has one of each (Bb), it will be a
red-factored black, which is a black capable of producing red. Every parent Doberman contributes either
a black gene or a red gene to it?s offspring. BB animals always contribute a B gene, bb animals always
contribute a b gene, and Bb animals contribute one or the other, with a 50% probability of each.
The second pair of genes we will discuss determine intensity of color. This pair of genes is called the
dilution factor, seen in black Dobes as blue, and in red Dobes as fawn. Because dilution is a recessive
trait, having the effect of lightening the color of blacks and reds, 2 of these recessive genes must be
present in order to express visible influence. We will call the LACK of dilution D, and the presence of
dilution d. A Doberman with DD will not show or be able to produce dilution. A Doberman with Dd will not
show dilution - it will be black or red, but it will be able to produce dilution. A Doberman that is dd IS a
dilute - a blue or a fawn. A Black Doberman with dd is a blue and a red Doberman with dd is a fawn.
dilution factor, seen in black Dobes as blue, and in red Dobes as fawn. Because dilution is a recessive
trait, having the effect of lightening the color of blacks and reds, 2 of these recessive genes must be
present in order to express visible influence. We will call the LACK of dilution D, and the presence of
dilution d. A Doberman with DD will not show or be able to produce dilution. A Doberman with Dd will not
show dilution - it will be black or red, but it will be able to produce dilution. A Doberman that is dd IS a
dilute - a blue or a fawn. A Black Doberman with dd is a blue and a red Doberman with dd is a fawn.
Homozygous means that the 2 genes of the gene pair match, as in BB or bb. Heterozygous means there is
one of each, ie, Bb, Dd.
one of each, ie, Bb, Dd.
Two more important terms are genotype and phenotype. The genotype is the Dobe?s genetic potential to
express a particular trait, in this case color. The phenotype describes how the Dobe looks - in this case,
Black, red, blue or fawn (or white - we will get to white in a minute.) There are 5 possible phenotypes.
There are 27 possible genetypes, but we will only discuss nine right now.
express a particular trait, in this case color. The phenotype describes how the Dobe looks - in this case,
Black, red, blue or fawn (or white - we will get to white in a minute.) There are 5 possible phenotypes.
There are 27 possible genetypes, but we will only discuss nine right now.
The first is a Black Doberman that can only produce Black offspring. This Dobe?s genotype is BBDD. It is a
DOUBLE HOMOZYGOUS (2 pairs of matching genes, ie BB, bb, DD, dd) dominant. This is referred to as a
#1 Black.
DOUBLE HOMOZYGOUS (2 pairs of matching genes, ie BB, bb, DD, dd) dominant. This is referred to as a
#1 Black.
The second is a Black that can produce Black and blue offspring. It is a homozygous black that ?carries? a
recessive dilution gene. (heterozygous - a non-matching pair of genes, ie - Bb, Dd) The genotype of this
Dobe is BBDd. It is referred to as a #2 Black.
recessive dilution gene. (heterozygous - a non-matching pair of genes, ie - Bb, Dd) The genotype of this
Dobe is BBDd. It is referred to as a #2 Black.
The third is a Black that can produce Black and red offsrping - It is heterozygous (Bb) for color, and
homozygous for intensity - in this case, DD - It can not produce dilution. This is called a #3 Black. It?s
genotype is BbDD.
homozygous for intensity - in this case, DD - It can not produce dilution. This is called a #3 Black. It?s
genotype is BbDD.
The fourth is a double heterozygous. It is heterozygous for color Bb, and heterozygous for dilution Dd. It
?carries? both a ?hidden? red gene, and a ?hidden? gene for dilution. It is called a #4 Black, and it can
produce black, red, blue and fawn. It?s genotype is BbDd.
?carries? both a ?hidden? red gene, and a ?hidden? gene for dilution. It is called a #4 Black, and it can
produce black, red, blue and fawn. It?s genotype is BbDd.
The fifth is a #5 blue. This is also a double homozygous. It is homozygous Black, BB, that is also
homozygous for dilution, dd. It can produce blacks and blues only. The genotype is BBdd.
homozygous for dilution, dd. It can produce blacks and blues only. The genotype is BBdd.
The sixth is a #6 blue. This Dobe is heterozygous for color, Bb. It is homozygous for dilution, dd. It?s
genotype is Bbdd and it can produce Blacks, reds, blues and fawns.
genotype is Bbdd and it can produce Blacks, reds, blues and fawns.
The seventh is a #7 red. This Dobe is also a double homozygous - bb makes it red. DD means it can not
produce dilution.
produce dilution.
The eigth is a #8 red. This red can produce dilution. It?s genotype is bbDd.
The ninth is a #9 fawn. This is a double homozygous recessive. It contains 2 pairs of recessive genes. bb
makes it red, and dd lightens the red, giving fawn.
makes it red, and dd lightens the red, giving fawn.
It is important to realize, that each parent contributes one gene FROM EACH PAIR to each of it?s offspring.
Therefore, each parent contributes one gene for color and one for intensity of color to each pup.
Therefore, each parent contributes one gene for color and one for intensity of color to each pup.
But how do you get white???
OK. Here?s how. The white is a Recessive trait. A Dobe must have both genes in the pair to . show white. This
pair of genes is a masking factor. What it does, is it hides the true color (and intensity of color) of the Dobe
containing this pair of genes. Because it is a recessive, a Dobe that is white, has the homozygous gene pair ww.
A Dobe that has the homozygous gene pair WW is not white, nor can it ever produce white. A Dobe with the
gene pair Ww is white-factored. This means that it ?carries? the masking factor as a hidden recessive.
pair of genes is a masking factor. What it does, is it hides the true color (and intensity of color) of the Dobe
containing this pair of genes. Because it is a recessive, a Dobe that is white, has the homozygous gene pair ww.
A Dobe that has the homozygous gene pair WW is not white, nor can it ever produce white. A Dobe with the
gene pair Ww is white-factored. This means that it ?carries? the masking factor as a hidden recessive.
Numbers 1-9 listed above may or may not be WW, Ww orr ww. Each of the nine above genotypes have three
possiblilities with respect to white. For example, a #1 Black, BBDD; A #1 black that is neither white, nor
white factored has a genotype of BBDDWW - It is a triple homozygous dominant. A #1 Black that is
white-factored has a genotype BBDDWw. A #1 Black that IS white, has a genotype BBDDww. This applies to all
nine of the genotypes.
possiblilities with respect to white. For example, a #1 Black, BBDD; A #1 black that is neither white, nor
white factored has a genotype of BBDDWW - It is a triple homozygous dominant. A #1 Black that is
white-factored has a genotype BBDDWw. A #1 Black that IS white, has a genotype BBDDww. This applies to all
nine of the genotypes.
In review, the three pairs of genes determining the color (phenotype) of your Dobe are; 1.) The color
genes, B and b. 2.) The intensity of color genes, D and d. 3.) The masking factor genes, W and w.
genes, B and b. 2.) The intensity of color genes, D and d. 3.) The masking factor genes, W and w.
Each and every Dobe will have a pair of each genes that may be homozygous (matching pair) or heterozygous
(mixed pair). If the genotypes of a pair of Dobes are known, the colors of their offspring can be predicted
with accurancy. The important thing to remember, however, is that predicted and actually seen to happen as
predicted are not always the same. For example, under normal circumstances, all offsping can be predicted to
be 50% male and 50% female. However, a perfectly even split is rarely seen. Same thing with color. If you roll
a six-sided dice 6 times, you are NOT LIKELY to roll each number once, although the probability of rolling any
particular number is always 1 in 6.
(mixed pair). If the genotypes of a pair of Dobes are known, the colors of their offspring can be predicted
with accurancy. The important thing to remember, however, is that predicted and actually seen to happen as
predicted are not always the same. For example, under normal circumstances, all offsping can be predicted to
be 50% male and 50% female. However, a perfectly even split is rarely seen. Same thing with color. If you roll
a six-sided dice 6 times, you are NOT LIKELY to roll each number once, although the probability of rolling any
particular number is always 1 in 6.
If you would like more information on coat color inheritance in the Doberman, please contact me and I will be
happy to help you figure out the genotypes and probabilities for color in your particular Dobermans.
happy to help you figure out the genotypes and probabilities for color in your particular Dobermans.
And PLEASE do not breed only for color! Breed for quality. Knowing what colors to expect is fun, but breeding
solely for color will prove detrimental to your line in the long run.
solely for color will prove detrimental to your line in the long run.
| "The Above was written by Lysa Rector, |