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Hi, 

I have a chocolate Merle border collie and I’m trying to understand her genetics. Her mum was a blue Merle and dad was a brown tri. From what I understand breeding Merle with Merle is bad because of the heath risks, but what colours are considered Merle and what colours aren’t Merle? Is it just the patterns or is any colour other than black and white considered a Merle? There was one deaf puppy in her litter and could the colours of both parents be the reason why?

Im not planning on breeding my collie, Im just interested in learning more and to know how to tell a responsible breeder from an un responsible one. 

Is lilac or wheaten or even black tri considered Merle or they can safely breed with a Merle? Or you can only safely breed a Merle with a black and white collie?

again I’m not planning on breeding I just am interested in understanding border collie colours. Thanks so much for your help!

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Merle is not a color. It's a pattern caused by a mutation on a gene (i.e. an allele) that dilutes whatever the base color is. The dilution is rarely uniform, so spots/areas of varying sizes of the base color will come through.

So a blue merle is a black dog with areas of the coat diluted to appear grey. A red (in border collies dark brown reds are still referred to as red rather than chocolate, at least among working border collie people. The rest don't count) merle's base color is red diluted with white hairs to look lighter. Ditto with all the other base colors.

Lilac and wheaten(?), Aussie red, blue (not blue merle but a slate grey color), etc. are colors that rarely occur in working border collies and are being bred for by what we'd automatically consider to be irresponsible breeders who select for unusual colors (and possibly other physical characteristics) over selecting for working ability, which, in the opinion of the Board's founders should always be the primary selection criteria for border collies. AKC or other KC breeders almost universally fall into this category and are rarely considered reputable breeders by the Boards' standards. (Read the Read This First section linked to in the introductory materials for the Boards.)

Merle to merle (homozygous) breeding is frowned on because dogs inheriting the merle mutation are at very high risk of deafness and blindness or other eye malformations.

Although the general opinion seems to be that merles have a much higher risk of deafness than solid colored dogs, deafness in heterozygous (i.e. inheriting only one merle allele) merles is only very slightly higher than in the general border collie population (search for discussions here on the Boards) and white headed dogs are also at higher risk. Lack of pigment in the inner ear is probably responsible for this and can occur even in dogs that are more conventionally marked. Other supposed health problems among heterozygous merles, AFAIK, is unsupported by evidence. There used to be similar wives' tales about red dogs as well.

There are tons of good sources online to learn about merle genetics. Merle is merle is merle no matter what breed or even mix the mutation occurs in, so some very excellent information can be found on Aussie sites because the mutation's so prevalent in the breed.

Edited by GentleLake
Correction of ass-backwards homo/hterozygous confusion.

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@GentleLake thank you for your help,  so would breeding a Merle and a dog with a slate colour have the same health risks and Merle to Merle?

 

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9 hours ago, Aisha_Zarla said:

...would breeding a Merle and a dog with a slate colour have the same health risks and Merle to Merle? 

No.

It can be confusing that both are referred to as a "dilution" but they're entirely different and unrelated genetic determinants. One set of genes determines the color of the dog. A separate modified gene (allele) determines how that color is expressed, in the case of merles, incompletely.

As I said, there's tons of information on color genetics available online for anyone who wants to get into it.

And FYI: "Merle" is not a proper noun, i.e. no capitalization -- unless it begins a sentence, of course. ;)

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GentleLake, sorry to correct you, but you have reversed the meanings of homozygous and heterozygous.

Merle is a codominant (incompletely dominant) mutation that can affect any base color of the dog (black, red, etc.).  One copy of the mutation paired with a normal gene (heterozygous) gives a dog the familiar mottled pattern we call merle.  Two copies of the merle mutation (homozygous) produces a dog that is mostly white in color, with varying degrees of blindness and deafness.

So if you breed two "normal" colored dogs, you will get all normal puppies with no chance of merle.  Remember, merle is codominant, meaning that it is always visible and is never hidden.  There are no "carriers" of merle, although a dog may be a "cryptic merle" meaning that the pattern is subtle and might not be noticed.

A merle dog mated to a normal non-merle dog will produce (on average) 50% heterozygous merle puppies and 50% normal puppies.  As GentleLake says, there is no risk of genetic defects related to the merle mutation in such puppies.

If you mate a merle dog to another merle dog, on average there will be 50% heterozygous merles with the mutant coat pattern, 25% homozygous normals, and 25% homozygous merles.  It is the homozygous merles that are mostly white, with varying degrees of vision and hearing loss.

Merle is extremely popular in Australian shepherds, and has been introduced into many other breeds of dogs:  dachshunds, great Danes, etc.  So the average dog owner is likely to come across merle dogs whether they know it or not.  Responsible breeders never breed two merles to each other, although some people are willing to do it if both merle parents have some outstanding complimentary characteristics.  Such breeders often euthanize any homozygous merle puppies, but sometimes don't since partial blindness and deafness can be hard to detect in young puppies.  Then you see ads on Craig's List for "Rare White Aussies!"

Obviously, this is disgusting and unethical, but probably no worse than breeding Cavalier King Charles Spaniels with skulls too small to hold their brains, or shar peis with eyelashes that grow inward and scar the cornea, or bulldogs with pelvises too narrow for normal birth--all puppies must be delivered by Ceasarian section.

In other words, welcome to the AKC!

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2 hours ago, Michael Parkey said:

GentleLake, sorry to correct you, but you have reversed the meanings of homozygous and heterozygous.

Don't be sorry!! Acknowledged and corrected. Thanks for catching it.

I think I have a little dyslexia, at least when it comes to these terms. I know the difference but I mix them up all the time. :blink:

 

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My understanding is that merle can be very difficult to spot in ee red dogs (aka wheaten or Aussie red dogs) and therefore it is considered dangerous to breed ee red dogs and merles, because of the risk that the ee red may be a cryptic merle, as Michael Parkey described.

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41 minutes ago, Lawgirl said:

My understanding is that merle can be very difficult to spot in ee red dogs (aka wheaten or Aussie red dogs)...

My understanding is that it's also very difficult to spot in sables, too. I don't think it's even so much that the dog may be a cryptic merle -- the very definition of a cryptic (aka phantom) merle is that it is that there's such a small dilution area that it's easy to overlook, even in black dogs -- as it is that the merling isn't very visible and may be overlooked, potentially leading to unintended merle to merle matings.

I've seen a sable merle Sheltie that most people wouldn't immediately recognize as a merle if they didn't know it. Because the sable is so light to begin with, the dilution areas barely stood out from the undiluted base color. Same with the Aussie reds and I suspect even with the double dilute slate/blue and lilac merles.

Btw, I suspected that a "wheaten" may be another name for an Aussie red. I just hadn't heard the term in the US.

 

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I think the term Aussie red came about because in Australia ee red dogs are just called red dogs by the ANKC crowd, while what you in America call red dogs, we call chocolate. But the ee red are also called wheaten by BYB and the uninformed, although I have also seen them called champagne, caramel or honey, essentially as descriptors for their colours, rather than as official coat colours.  I recently got told off in a Facebook group in Australia for calling one of my dogs a red merle and not a chocolate merle...

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I think you're probably right, @Lawgirl. Does the ANKC still have limited colors they recognize that causes people to incorrectly identify the odd colors as the closest approximation just so they can have them registered?

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On 6/29/2019 at 3:54 AM, GentleLake said:

 Does the ANKC still have limited colors they recognize that causes people to incorrectly identify the odd colors as the closes approximation just so they can have them registered?

Not since July last year. They finally updated the breed standard to allow "a variety of colours but white should never predominate".  Up until then, you could have blue merle, but not red merle in a pedigree dog, so red merles were registered as chocolate and white, for example.

Although I have never owned a pedigree dog, I think they also changed the standard to include short coat and erect ears at the same time.

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3 hours ago, Lawgirl said:

I think they also changed the standard to include short coat and erect ears at the same time.

The idea that anyone would consider erect ears a fault or worse, disqualification, in border collies just boggles my mind. :rolleyes:

Smooth coat for that matter too.

It's like they never looked at the breed they chose to include in their registry before they did it. :blink:

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Erect ears were definitely a fault, and I think blue eyes were too, although blue eyes are allowed in merles now.  Technically floppy ears still are, and heterochromia is too.

But that is the problem with a breed standard - when you have to decide what "looks right" you also have to decide what looks wrong, which is everything else...

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3 hours ago, Aisha_Zarla said:

This is all so confusing :lol: haha

You have somewhat innocently provided an outlet for one of the more complicated topics on this forum - the conflict between working border collies and their owners, and the Kennel Club/Fashion Show breeders, aka those who breed BCs for working ability and those who breed for looks.  This forum is solidly on the side of the working ability of this wonderful breed.

We ended up stealing your thread. Sorry!

So the TL;DR version is that merle is a coat pattern that dilutes sections of a dog's coat giving a mottled effect, but which can apply to any of the coat colours (black, tricolour, red/chocolate, ee red, etc).  It can be "cryptic" or in very small patches.  Some coat colours can make it very difficult to see the merle pattern, usually because the coat colour is very pale.  So great care should be taken in breeding a merle dog to be ensure the other dog is not a cryptic merle, and dilute colours like lilac and blue, and pale colours like ee red and sable, should probably be avoided. And of course, never breed two merles!

PS if you have not already done so, we love photos of your dogs here!

 

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Thank you so much, I have enjoyed trying to learn more about this! 

Heres a couple photos of my BC :D

EB5B9875-5F15-40ED-81BA-FF38608DF817.jpeg

0F0267F6-CB28-41E2-83D8-EF437371E368.jpeg

81BD4A67-38ED-4EF9-BCCC-0587CC5A02A2.jpeg

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2 hours ago, Lawgirl said:

Your girl is gorgeous, and looks like a very happy pup!

Thank you! She’s amazing, she’s my first BC and is very different to my blue heeler. Definitely has a strong personality which I love ^_^

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21 hours ago, Aisha_Zarla said:

Thank you! She’s amazing, she’s my first BC and is very different to my blue heeler. Definitely has a strong personality which I love ^_^

Welcome to the Boards, and to your new addiction!

I see you are from South Australia.  I am not sure, but we may be the only South Aussies on here! Whereabouts are you in SA?  I live in Mount Gambier, so am in the south east corner of the state.

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3 hours ago, Lawgirl said:

Welcome to the Boards, and to your new addiction!

I see you are from South Australia.  I am not sure, but we may be the only South Aussies on here! Whereabouts are you in SA?  I live in Mount Gambier, so am in the south east corner of the state.

Oh cool! Do many Aussie’s use this site? I live north of Adelaide! Where it’s starts to be the country :D 

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There are a few of us Aussies, but not too many.  This is an American forum after all.

I lived in Gawler all through my high school years, and my brother and sister went to high school in Tanunda, so I know the north of Adelaide fairly well, or at least I did lo these many years ago...

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On 7/5/2019 at 9:51 AM, Lawgirl said:

There are a few of us Aussies, but not too many.  This is an American forum after all.

I lived in Gawler all through my high school years, and my brother and sister went to high school in Tanunda, so I know the north of Adelaide fairly well, or at least I did lo these many years ago...

Oh is it aha I didn’t realise! :)

oh really! That’s where I live atm, I used to live further out but didn’t want to always drive 40 minutes to get to places ahaha. Tanunda is a beautiful place, what a small world! :) 

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