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 Post Posted: Fri Feb 13, 2009 1:36 pm 
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OK y'all, brace yourselves :)) After researching this for a year, watching several litters develop, comparing historical notes and talking to a canine color geneticist, I'm ready to unleash my comprehensive thoughts on Lacy coat color genetics! Of course, this is just a general guide, Lacys could have breed-specific modifiers tweaking the results. And some alleles are touchy and act in strange ways when combined with one another. But until we do genetic testing for color, I'm told this is a very solid guess. Just remember, one magical "blue gene" does not exist, and you'll see why by the time we make it through all the alleles.

First things first. Genes always come in pairs, and dogs get one gene from mom and another from dad. Likewise, mom and dad each get one from grandma and grandpa. It is possible for recessive genes to be passed down for several generations that never express themselves. So, for the most part, there is no way to guarantee color results. Also, keep in mind that diversity in color genes is healthy, especially for dilute dogs. Don't breed to get a certain color, put the health and performance of the dogs first.

Coat color is all about melanin. Eumelanin is black/brown and pheomelanin is red. White represents the lack of melanin. I'm only dealing with melanin here, not white, because it appears most Lacys have a unique spotting modifier.

A, the Agouti locus, decides whether a Lacy is solid or tri. Lacys probably carry A, the solid eumelanin gene, or at, the eumelanin pointed with pheomelanin gene. Because the A is dominant, an Aat will appear solid. You must have two tri genes, atat, to get a tri. It is possible that some red Lacys carry an ay, but it's unlikely, and I'll explain the possible faults it would produce later. If we discount the ay gene for now, we see three possible starting points for Lacy color.

AA - solid (blue, gray, red, yellow, cream)
Aat - solid carrying tri
atat - tri

Next up is B, the Black locus. This is where the fate of eumelanin is decided. And the primary method of differentiation is the nose leather. Most Lacys carry at least one B gene and are black. But it appears that chocolate, bb, base does exist in Lacys, as is noted by the possibility of liver/tan/brown noses. Yes, reds do carry B or b genes, but they are modified later on. A red or yellow Lacy with a brown nose is bb.

BB - black (blue, blue tri, red, yellow, cream)
Bb - black (blue, blue tri, red, yellow, cream)
bb - brown (gray, gray tri, red, yellow, cream)

And this is the gene you've all been waiting for. Dilution! This is what takes black and chocolate dogs and turns them into blues and grays. Though it wasn't long ago that blacks were still in the gene pool, selective breeding for dilution has solidified the trait, so now all dogs carry dd at the D allele. Though it has a slight impact on pheomelanin, dd primarily affects eumelanin. It's important to note that because both black and chocolate are eumelanin, they dilute to very similar shades. The main way to tell the difference is the nose colors.

dd - dilution (all colors)

So how do we get red, yellow and cream? The suppression of eumelanin so that only pheomelanin is expressed. This could originate at A with an ay, but it definitely occurs at the E locus. Again, E is dominant, meaning the dog only needs one E to produce eumelanin. If a dog is ee, they only express pheomelanin.

EE - eumelanin expressed (blue, blue tri, gray, gray tri)
Ee - eumelanin expressed, suppression carried (blue, blue tri, gray, gray tri)
ee - eumelanin suppressed (red, yellow, cream)

The C locus effects the different shades of red and red points on tris. In Lacys, C works on pheomelanin in a similar way to D on eumelanin. However unlike D, it does not affect the shade of the nose leather. C is responsible for the deepest shades of red. The palest shades are ch. C seems to be incompletely dominant, so Cch dogs would be lighter, probably yellow, but not cream. Interestingly, chch dogs are born almost white and darken throughout their lifetime, while CC are born darker and lighten as they get older.

CC - full pheomelanin (darker red)
Cch - moderate pheomelanin (lighter red, yellow)
chch - diluted pheomelanin (cream)

The best way to see how these genes work is to look at specific dogs, their parents and their offspring. Let's start with Brutus and Abby, a father and daughter with very different phenotypes:

Image

Brutus is Aat/bb/Cch/dd/ee and Abby is atat/Bb/Cch/dd/Ee.

Why? Brutus carries at because his father was a tri and he produced a tri daughter. His brown nose means he is bb. He has moderate pheomelanin expression, and he produced a cream, so he is a Cch. We know he is dd due to his dilute offspring. We can see he has no eumelanin and is ee.

Abby has to be atat because she is a tri. Her dark nose means she's Bb because she got a B from her mom Heidi that overrides the b from Brutus. Her red points are almost identical to her dad's shade plus we know her aunt Secret was a chch cream, so she is probably Cch. We can visibly see her dd dilution in her blue base. And because she expresses blue but comes from a red, she is Ee.

Now who has questions :p Please post examples or comments, because I'm going to make this into a photographic guide featuring different combos.

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"You must be a very small minority no matter who you hang around with. Maybe you should start a magazine, Vegetarian Hog Dogging Monthly, find some like-minded individuals."
- Inspiration for my next project from TBH

True Blue Lacys: http://www.truebluelacys.com
More Lacy Pics: http://www.flickr.com/photos/julieanna/sets/72157605027566732/


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 Post Posted: Fri Feb 13, 2009 2:06 pm 
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"Now who has questions"

Id like to know why hog dogs are wearing pink collars?

Steve

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 Post Posted: Fri Feb 13, 2009 2:31 pm 
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Why do I feel like I'm back in college? I'm going to Amazon.com and ordering "Genetics for Dummies". I

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 Post Posted: Fri Feb 13, 2009 3:27 pm 
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It's rare, but I've seen that pink collar gene in a couple hog dogs. Incidentally all of them were owned by women, so maybe it is a matter of nurture over nature ;;)

One thing I forgot to add... a dog can be a tri, atat, but still be red. If they also carry the ee gene, the eumelanin in the tri pattern will be suppressed and the dog will look like a solid red. Though I've heard that if you look really close, sometimes the eyebrows and other pointed areas will be a different shade.

This is one reason the tri gene continues to get passed down, because some of the reds are genetically tri. It certainly makes things a little more difficult if you try to predict colors. Also, if you breed a tri to tri, all the pups will be atat. But if the parents were both Ee, some pups could be ee. An atat/ee will appear to be solid red. So a tri x tri litter could have tris and reds, but there won't be any blues.

_________________
"You must be a very small minority no matter who you hang around with. Maybe you should start a magazine, Vegetarian Hog Dogging Monthly, find some like-minded individuals."
- Inspiration for my next project from TBH

True Blue Lacys: http://www.truebluelacys.com
More Lacy Pics: http://www.flickr.com/photos/julieanna/sets/72157605027566732/


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 Post Posted: Fri Feb 13, 2009 4:08 pm 
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I just finished some Catia programming for my CNC machining class and then I go and read this. Now my head aches! :)) Give me some time to absorb it. So basically there are red tris out there but they just don't show through that well in some dogs? THAT I can understand. I believe I did see a liver tri lacy when I went with my friend to the breeder in Old Dime Box, TX when he selected a blue pup that was from one black parent and one blue parent. There was another lacy there in a pen by himself that looked to be a liver tri color. Sort of like doberman red in color but with the eye marks and all that.


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 Post Posted: Fri Feb 13, 2009 4:32 pm 
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pink collars...huhm...next thing you know, you will be dipping some organic stuff from Whole Foods....

Jerryg


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 Post Posted: Fri Feb 13, 2009 4:49 pm 
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jerryg wrote:
pink collars...huhm...next thing you know, you will be dipping some organic stuff from Whole Foods....

Jerryg


Next time I see you, I'll kick you in the cods rather than shake your hand!

Steve

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Remember the dog wags the pedigree and the reverse is not true.

16, intelligent and articulate, I'm a fan!


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 Post Posted: Fri Feb 13, 2009 5:02 pm 
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Very interesting... Presently, it looks like all the Lacys in our gene pool are dd. With dd, chocolate dilutes to gray, just like Weimeraners. Depending on different modifiers affecting the shading and degree of dilution, a blue-based tri (atat/B_/dd) should look almost identical to a gray-based tri (atat/bb/dd), but the nose leather will be different. These puppies are the perfect example:

Image

See the different noses? The blue is Aat/B_/dd (his mom was a tri and he could be BB or Bb because the black is dominant). The tri has atat/bb/dd genes. The difference is usually most noticeable in pups and even then it can be hard to tell since dd dilution does affect the nose leather.

But yes, I keep reading that there was black ones, and I do believe they meant true black, not dark gray. Do you know if that liver-ish tri was out of the black parent? Because that would actually be possible. If a bb didn't get the full dd for dilution, their eumelanin would be brown. I'm not sure how the D was so effectively eradicated, but I've never seen or heard of a black pup.

_________________
"You must be a very small minority no matter who you hang around with. Maybe you should start a magazine, Vegetarian Hog Dogging Monthly, find some like-minded individuals."
- Inspiration for my next project from TBH

True Blue Lacys: http://www.truebluelacys.com
More Lacy Pics: http://www.flickr.com/photos/julieanna/sets/72157605027566732/


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 Post Posted: Sun Feb 15, 2009 10:16 am 
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Julie,
Please help me out with this one...I went to see a litter of Lacy's here in Florida several years back. Both parents were blue with black noses. It was a fairly large litter if I recall correctly, I'm thinking at least 8-10 pups There was a blue, no tris and the rest of them were the most beautiful champagne color or very very light silver but all had a reddish nose. They were very nice pups but I shied away from them because of the reddish nose. The breeder said they'd only had very few red pups in the previous litters and she was surprised to see all of these cream pups. I regret not getting one now as I've heard really good things about this litter. Sire/dam were fixed just after this litter because these people had very very young children and not enough time.
Since this time I've seen other pictures of Lacy litters that were predominantly this creamy color but until I saw pics of Secret I never knew this was an acceptable Lacy coloration.
Rebecca


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 Post Posted: Sun Feb 15, 2009 1:25 pm 
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We have not ever had a litter that big BUT we have had litters with well mixed
colors. A couple blues, reds tris & creams. The attached pic is of a litter that originally had
6 pups. The Dam (Hidie) laid on 2 of them, a blue and a tri. That left the 4 in the pic
I have the Tri female in the pic
Abby
Image

However when we bred Secret she had an all blue litter. Secret & Hidie were litter mates..full sisters.
Hidie & Secret when they were pups
Image

~Mis


Attachments:
IMG_0005.JPG
IMG_0005.JPG [ 23.38 KiB | Viewed 1598 times ]

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Bayed Blue...Bayed True...That's A Lacy Dog
If You can't keep up with the Lacy Dog...stay on the porch!
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 Post Posted: Sun Feb 15, 2009 4:05 pm 
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Rebecca, that sound like a very pretty litter. It would be rare to have a lot of creams, because you need two sets of homozygous genes to get it, chch and ee. You need another set of homozygous genes to get the grays with pinkish noses, bb and dd. All Lacys carry dd, but not all have bb, chch or ee. So they really hit the genetic lottery with those pups.

The ones that came out gray were most likely AA/bb/(Cch or chch)/dd/(EE or Ee), the key combo being bb/dd. The cream pups were AA/(Bb or bb)/chch/dd/ee, with chch/ee being the important combo there. All of those are acceptable varieties, but because they involve a couple homozygous genes, you can see why they are less common. I'm not surprised this was there first litter like that and I bet they wouldn't have been able to reproduce it.

How old were the pups when you saw them? Cause creams are born very light and will darken as they get older. So they may start with pink noses but those could darken to either diluted brown or diluted black. And the pink noses on the grays would eventually darken to a dilute brown.

_________________
"You must be a very small minority no matter who you hang around with. Maybe you should start a magazine, Vegetarian Hog Dogging Monthly, find some like-minded individuals."
- Inspiration for my next project from TBH

True Blue Lacys: http://www.truebluelacys.com
More Lacy Pics: http://www.flickr.com/photos/julieanna/sets/72157605027566732/


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 Post Posted: Sun Feb 15, 2009 6:14 pm 
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They were about seven/eight weeks old. I was so so tempted to get one but I had just gotten Amos and didn't want to raise two pups at a time. I took pictures of them but unfortunately they are on my harddrive that is sitting on the shelf. I was just amazed at the shimmer in their coat and how each one was just a little different in shade. Gorgeous healthy pups. If I ever get my computer set back up I'll post them. The breeder had both the parents fixed after this litter because they had two very small children and just no time. So I missed my opportunity for an usual color.

Also, what happened to Secret? I always loved pics of her. Her coat looked like creamy velvet.

oh, and another question. Why are some Lacy's eyes browner than others? Amos has very most golden eyes; his sister, Sweet Honey has the exact same eyes. But I've noticed that some Lacy's eyes are much browner. Does the brown run in certain bloodlines?
Thanks
Rebecca


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 Post Posted: Sun Feb 15, 2009 9:24 pm 
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Hey Julie I have a creme male I want you to look at that is out of two blues one was a bluer blue and the other was a browner looking blue. They the dam and sire never threw a blue tri color but I swore they threw red tri's I have even called Jimmy and Marlo years ago and asked them about the possibility of it. It was very difficult to see but you could. I had around three of them (tris)all together.I will dig around for a pic of one of them.Image


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 Post Posted: Mon Feb 16, 2009 11:16 am 
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Thanks for all your hard work on this, Julie! Aaron, Amanda, DJ, and I were stuck in a car together for several hours yesterday and we read your post several times and discussed it for a long time! We were able to determine a lot about the color genes of our dogs and we know now that we can predict the colors of future litters with much more accuracy. I look forward to hearing more about the genetics of the white on Lacys.

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 Post Posted: Mon Feb 16, 2009 12:16 pm 
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Take a look at Mike Anderson's lacy pics on the TLGDA photo albumn. He's had several pups that looked to be red tri (now that I know what I think that is supposed to be). There is a pic of a dog "Rosey". I don't know his bloodlines but his pups have been very successful at hunting and tracking.
Rebecca


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