| D Locus |
| Lesson #6 will be based on the D Locus. The D Locus attained it's name from the word Dilute. |
Blue and White Boston Terriers, also known as grey or silver and white, are currently hands down the most
popular of the non-traditional colors of the Boston Terrier rainbow. This diluting of the eumelanin hair and
pigmentation causes a black and white Boston to become blue. With research it has been found that there
are more than one mutation of the dilution gene, however, they have yet to map which alleles and how
many. We do know that this dilution occurs on Chromosome 25 in canines.
Puppies are usually born a light to medium blue and darken with age. Also, blue puppies tend to have iris
color that is grey and darken to a brown into adulthood. There are some blues that do stay lighter colored,
some with heavy brindling that is also a diluted color that can be compared to cream colored brindling, and
they do retain an oddly colored greyish hazel iris'. Most adult blues will be found in the hue of a medium to
dark steel blue, with dilute pigmentation to match the coat. Again, the blues that seem to stay the lightest
are the blue Boston Terriers with the heaviest brindling, as the cream color of the brindle lightens the coat.
This is not a pattern of blue that is predominant.
Nose Color: Dark Blue
Eye Color: Dark Brown, at times Grey Hazel
popular of the non-traditional colors of the Boston Terrier rainbow. This diluting of the eumelanin hair and
pigmentation causes a black and white Boston to become blue. With research it has been found that there
are more than one mutation of the dilution gene, however, they have yet to map which alleles and how
many. We do know that this dilution occurs on Chromosome 25 in canines.
Puppies are usually born a light to medium blue and darken with age. Also, blue puppies tend to have iris
color that is grey and darken to a brown into adulthood. There are some blues that do stay lighter colored,
some with heavy brindling that is also a diluted color that can be compared to cream colored brindling, and
they do retain an oddly colored greyish hazel iris'. Most adult blues will be found in the hue of a medium to
dark steel blue, with dilute pigmentation to match the coat. Again, the blues that seem to stay the lightest
are the blue Boston Terriers with the heaviest brindling, as the cream color of the brindle lightens the coat.
This is not a pattern of blue that is predominant.
Nose Color: Dark Blue
Eye Color: Dark Brown, at times Grey Hazel
| Blue and White Genetically Known As: d/d ***These Boston Terriers are NOT Seal and White*** |
Lilac and White Boston Terriers, also known as blue-fawn or champagne and white, is a close second for
favorite among the fanciers of todays non-traditional colored Boston Terriers. At times there are those that
will get the blue and lilac colors confused, but when comparing the two side by side there is no confusion.
Lilac is actually a dilute of brown, and obviously to produce this color there must be a pair of recessive
brown alleles and a pair of recessive dilute alleles. If the brown genes are not present all that results are
dilute blacks or blue Boston Terriers. If the dilute genes are not present all that results are brown Boston
Terriers. Lilacs are so named because of their genetic coding, because they are the mixture of brown (red)
and blue, those colors make just that....LILAC!
When born, lilac Boston Terriers are very purple/blue in hue and once their pigment fills in the lilac color
can be seen on their nose as well. It is distinctly different from the silver color of a newborn baby blue. As
with blues, lilacs do tend to darken with age as well but no where as dark as some blues can become, but
they keep that purple sheen to their coat. As there have been more dilute brown Boston Terriers being
born we are seeing different shades in them as well. There seems to be certain dilute browns that do not
have as strong a mixture of blue coloring in their coat so they appear to be a very pale washed out red
color, this color has been termed champagne.
One very important note to make when looking at lilac Boston Terriers is that when their eyes first open the
iris color is a bright blue color. This color blue usually lasts until they are several weeks old, possibly
months depending on the puppy, then the iris color changes to a crisp green. Most all of the time into
adulthood the iris color has changed from the green hue to a light yellow color that is most beautiful. Just
like with any color of Boston Terrier, there are those blue eyes that do remain crystal blue for the life of the
Boston.
Nose Color: Lilac to Pale Red
Eye Color: Green to Pale Yellow
favorite among the fanciers of todays non-traditional colored Boston Terriers. At times there are those that
will get the blue and lilac colors confused, but when comparing the two side by side there is no confusion.
Lilac is actually a dilute of brown, and obviously to produce this color there must be a pair of recessive
brown alleles and a pair of recessive dilute alleles. If the brown genes are not present all that results are
dilute blacks or blue Boston Terriers. If the dilute genes are not present all that results are brown Boston
Terriers. Lilacs are so named because of their genetic coding, because they are the mixture of brown (red)
and blue, those colors make just that....LILAC!
When born, lilac Boston Terriers are very purple/blue in hue and once their pigment fills in the lilac color
can be seen on their nose as well. It is distinctly different from the silver color of a newborn baby blue. As
with blues, lilacs do tend to darken with age as well but no where as dark as some blues can become, but
they keep that purple sheen to their coat. As there have been more dilute brown Boston Terriers being
born we are seeing different shades in them as well. There seems to be certain dilute browns that do not
have as strong a mixture of blue coloring in their coat so they appear to be a very pale washed out red
color, this color has been termed champagne.
One very important note to make when looking at lilac Boston Terriers is that when their eyes first open the
iris color is a bright blue color. This color blue usually lasts until they are several weeks old, possibly
months depending on the puppy, then the iris color changes to a crisp green. Most all of the time into
adulthood the iris color has changed from the green hue to a light yellow color that is most beautiful. Just
like with any color of Boston Terrier, there are those blue eyes that do remain crystal blue for the life of the
Boston.
Nose Color: Lilac to Pale Red
Eye Color: Green to Pale Yellow
| Lilac and White Genetically Known As: b/b d/d ***These Boston Terriers are NOT Seal and White*** |
- With dilutes of any breed there are always questions about skin and coat health. Dilute Boston Terriers do
naturally have a lower hair count per square inch as opposed to their black and white counterparts. There
have been instances of dilute Boston Terriers with possible mange and skin/coat allergies. It is important
to note that there are Boston Terriers of all colors, even black/brindle or seal, that have the same issues.
The only skin/coat condition that dilute Boston Terriers may develop is Color Dilution Alopecia or CDA.
There is no test for CDA, so even if a dilute Boston Terrier presents with symptoms of this issue, there is
no way to confirm.
- It was once believed that all blue to blue breedings of Boston Terriers should results in 100% all blue
puppies. New findings have proven that there is more than one mutation of the dilute gene, therefore with
these findings researchers have concluded that there is a possibility that when breeding two blue Boston
Terriers, a dominant black may result. The only way this is genetically possible is if both parents, even
though they are blue, are genetically D/d, carrying one copy of a dominant D and one of a recessive. If the
mating takes place and the D genes line up, there will be a black puppy born in the litter. This is highly
unlikely and the chances of this happening are extremely low. To date there has been one female blue and
white Boston Terrier that was DNA color analyzed by VetGen laboratories who resulted in a genotype of
D/d for the D locus test. Her sire and dam were visibly blue and all siblings in the litter were also blue.
This female has been bred to a confirmed d/d tested male and all puppies born were blue, all testing d/d.
It is by far a great genetic anomaly.
-In the rare case two dominant colored Boston Terriers who do not carry recessively for dilute produce a
dilute, it can be explained. It is understood a mutation at chromosome 28 causes the dilution of pigment
and coat color. In this event, it is likely that this will not happen again between the two parents as this is a
one in a million mutation. This is how it is believed that the first blue and white Boston Terrier in history
came to be. This dog was known as the Perry dog, said to have been imported from Scotland and
incorporated into the foundational bloodlines.
- Lilac is the only color other than red/brown that has ever been proven to have been produced in a mating
of a pair of red/brown b/b Boston Terriers of true lineage, purebred, and DNA verified parentage.
naturally have a lower hair count per square inch as opposed to their black and white counterparts. There
have been instances of dilute Boston Terriers with possible mange and skin/coat allergies. It is important
to note that there are Boston Terriers of all colors, even black/brindle or seal, that have the same issues.
The only skin/coat condition that dilute Boston Terriers may develop is Color Dilution Alopecia or CDA.
There is no test for CDA, so even if a dilute Boston Terrier presents with symptoms of this issue, there is
no way to confirm.
- It was once believed that all blue to blue breedings of Boston Terriers should results in 100% all blue
puppies. New findings have proven that there is more than one mutation of the dilute gene, therefore with
these findings researchers have concluded that there is a possibility that when breeding two blue Boston
Terriers, a dominant black may result. The only way this is genetically possible is if both parents, even
though they are blue, are genetically D/d, carrying one copy of a dominant D and one of a recessive. If the
mating takes place and the D genes line up, there will be a black puppy born in the litter. This is highly
unlikely and the chances of this happening are extremely low. To date there has been one female blue and
white Boston Terrier that was DNA color analyzed by VetGen laboratories who resulted in a genotype of
D/d for the D locus test. Her sire and dam were visibly blue and all siblings in the litter were also blue.
This female has been bred to a confirmed d/d tested male and all puppies born were blue, all testing d/d.
It is by far a great genetic anomaly.
-In the rare case two dominant colored Boston Terriers who do not carry recessively for dilute produce a
dilute, it can be explained. It is understood a mutation at chromosome 28 causes the dilution of pigment
and coat color. In this event, it is likely that this will not happen again between the two parents as this is a
one in a million mutation. This is how it is believed that the first blue and white Boston Terrier in history
came to be. This dog was known as the Perry dog, said to have been imported from Scotland and
incorporated into the foundational bloodlines.
- Lilac is the only color other than red/brown that has ever been proven to have been produced in a mating
of a pair of red/brown b/b Boston Terriers of true lineage, purebred, and DNA verified parentage.
| ***Important Facts To Note About Blue/Lilac Boston Terriers*** |
| I am ready to move onto Lesson #7: Hypothetical C Locus Please Take Me To Lesson #7 Please Take Me To Color Home |
