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Discussion Starter · #1 ·
OK ........Lucky me and others

i'll repost what i had up ok? sorry
but i am going to start at basics instead and then work up to the colors
of Black/Brown/ red/cream/apricot etc

as Tink's reaction made me realize we need to start at alleles, agouti and so on first
 

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Discussion Starter · #4 ·
OK since we're all at different levels and with different interests and/or questions let's start with real basics working towards the different colors and crosses

Every dog has 78 chromsomes....38 are homozygous (same) pairs.
NOW each GENE contains thecodes/units of inheritant factors of DNA that are located on the chromosomes.
And allele is a alternative form of a gene that is positioned on a specific spot on a chromosome.

so what is this postion or place where its located on a chromosome called?
answer: LOCUS
now we get into
Dominant and Recessive genes
B for black is dominant...CAPITAL LETTERS means dominant
LOWERCASE letters means recessive
so B stands for black dominant
b stands for chocolate recessive
but some recessives genes when present as in "ee" or "bb" can override dominant genes ( to be discussed later)
whereby the recessive genes now have a dominance OVER dominant genes

now Genotype is the genetic makeup and Phenotype is what we seeie:
Bbee is a red dog with a black nose
Genotype: Bbee
Phenotype: red color coated dog with a black nose

Oh now melanin is a skin pigment that determines a dog's body and hair shaft color
There are 2 kinds of melanin:
1. eumelanin which produces dark pigment such as black/brown
2.phaeomelanin which produces yellow/red color

OK here is where Agouti comes to play
Agouti is a protein that now creates banding of colors.
or simply put is how color is determined in a dog's coat

(some trivia: 'Agouti' term is named after a South American rodent that is an example of this type of hair.)

i'll stop here and then go on the next section which will be
B locus, E extension locus,
remember some books might say B or E Allele
it's the same thing :wink:
 

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Ok...the extension focus and allele being the same thing solved one confusion for me, thanks!!
 

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I am with you on all the B, b, E, e stuff. B= Black. b= brown. B dominates b. E means the dark colour is made, e means it isnt, so thats where it gets fuzzy for me. I studied the B stuff more because I have a black and chocolate doods. But....within the E series, what determines the depth of colour? ie, a white, yellow, apricot, red are all ee. whats the deal with that?
 

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Yea, What's the deal with that???????

(Just razzin" you, Annmarie!!!)

I could have explained it last week.....but it's gone!
 

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Discussion Starter · #8 ·
OK e part is alot of fun ........want me to start at top?
 

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Discussion Starter · #10 ·
the Extension Locus E , it also will involve the others like A, C, and more
so bear with me

ee means red but not always a red like Beau, ee can also be a sable, apricot, white, cream, because there are other color determining factors and most DNA tests do now reveal the hidden or recessive genes carried
Thus many just do B, b, E, e

so let's go with all of them and have some fun
i understand MOST of this to-date.

in reality the e means it can dominate/suppress the dark pigment

so they use "e" to mean recessive yellow which includes
red, cream, apricot,sable, golden and white can squeak in here too

Both the E allele and Em allele are responsive to agouti
OK, now dogs that are genetically "e/e" have a mutation in MC1R and produce only phaeomelanin so they end up some shade of red,yellow/golden/cream.

alright LISTED BELOW are the loci that play a role along with E for color regulation and distribution thus the genotype affects the phenotype
so
The generally recognised color series (loci) in dogs are called:
A (agouti)
B (brown),
C (albino and concentration)
D (blue dilution)
E (extension)
G (graying)
S (white spotting)
W (white)
***I left out Raon, Ticking, and Merle and also Parti etc

Agouti the "A" plays a big role in how a color is determined on a dog's body
it is controlling the distribution of coloring on a dog's hair shaft

So ay/ay is a true red with NO black in it's hair anywhere and Usually also red whiskered (this is still theory on the whiskers part)
(NOTE: LOCI is plural for locus) :wink: 8) :wink:

summary one:
A and E loci are involved with controlling or setting forth the pigment of hair color distribution/patterns

B,C,D,G and M loci
can change patterns by diluting them

S loci are involved with the distribution/placement of white

lastly
it is believed in the Agouti or rather most books suggest that it is
ay > aw > at > a

NOW you'll see how easy this gets from here on in

i'll wait for a reply from you and any questions that might stretch mhy brain and maybe i'll learn even more :D
 

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Discussion Starter · #11 ·
another way to look at this is

A is a modifier
B is self-color
C is a modifier
D is a modifier

E is a melanin producer of pigment
G is a modifier
S is a distributor
W is a modifier


now back to Agouti

a^b=recessive black
a^y = restricts dark pigment distribution
a^w = agouti "wild-type" allele which can give a grey coloration aka a^g
a^t = a bicolor allele----tan point allele which can gives bicolored animal (such as black/tan coloration)
a^s produces black

now there are other loci that can further affect the E and A
meaning how we see partis, or dogs with white markings, or even chocolates that silver , blacks that are blue and etc
 

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Discussion Starter · #12 ·
you now can have ay/ay or ay/at and so on

ay/ay produces deep true clear red that doesn't fade
ay/at produces sable red that has some black in it even if it isn't visible
as AGOUTI has banding color on the hair and hair shaft

separate the hair and sometimes you can see this

Agouti affects how black and red/yellow/tan is
or rather controls the depth of color and placement of color on the hairs of the dog.

now just "A" is dominant black as you would see in labrador retrievers
 

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Annmarie if I ever decide to get into breeding
I will get you to pick the dogs for me....................
Great research and although interesting it is way over my head
so Thank Goodness you get it.......................and I can tell you love it
:wink: :wink: :wink: :wink: :wink: :wink: :wink:
 

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Discussion Starter · #14 ·
hahhahaa Thanks SUE and YES I LOVE Genetics ...loved it back in high school and in college
wait till i get to charting the combo's out
and am going to ask for pics of chocolate dogs with other colors that set in when they mature like blonde and silvering like how weimeriemers looks
I can't spell that dog breed's name if my life depended on it!

ok BACK TO Genetic schoool now hahhahaaaaaaaa
 

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Okay,,so I have Labradoodle, who's DNA results came back as bbEe

That is chocolate carrying the resessive gene for yellow, meaning apricot, cream, am I right so far? She also has a white chest, and her chocolate color has changed to a much lighter coat with white hairs throughout, and I think that is called kemp. As it is a more stiff white hair. Shouldn't she have an agouti coloring somewhere......? or am I totally confused on that?
 

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Discussion Starter · #18 ·
TRINA....ok chocoloate Labradoodle
bbEe...liver nose right?

i am going to continue on a bit as it will tie in the colors you mentioned
I am not sure about "KEMP" are you able to do any searches on that for curiousity sake?

also is the white PURE WHITE or is a Silvering effect happening almost like the sheen of the DOG IN THE TREE GENE luckily posted along with the right spelling (THANK YOU GENE! hahahhaa that is one my fav pics too)
 

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Okay here is a picture of her,,,and then just a picture of her hair along her back and side

IMG]http://i70.photobucket.com/albums/i83/just4me89/IMG_0262.jpg[/IMG]



and as I was really looking at her,,maybe it is not kemp, maybe it's just some silvering....I'm going to research kemp and post what I find...
 
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