While this blog speaks often of genetics and shepherd dogs, coat color genetics holds little interest to me save when it represents a moral issue. But, coat color genetics is perhaps the most popular interest of dog breeders, mostly because they want to know how they can get that pretty color in their litters. So, coat color aficionados, can you solve this puzzle?
Here are photos of a sire and dam, and their puppies. How can two parents that display white markings produce puppies that don’t?
The Sire
The Dam
Their Puppies
Where are the white markings?
Leave your theories in the comments, please.
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This is a situation for dna parentage test. The only explanation other than wrong sire is the rare situation where on or the other parent is a genetic chimera – fusion of two embryos – and the gonads are from the black masked self colored sable red embryo which is otherwise has a minimal presence in the adult parent.
The black and tan color of the one pup is recessive to the sable red color so its presence as a color is not indicative of a mis-assignment of parentage. However the extreme self pattern in the pups is not, based on current understanding of dog white marking inheritance, what you could get. As the pups get a little older one other thing to look at is coat length. In general longer coats are recessive to shorter coats. I have linked to an older page I did on coat color inheritance in dogs. I need to update it but the basics are still, as far as I know, correct. http://borzois.com/coat.color/coat.color.html
If only one pup was self then there would be a possibility of a mutation to self from irish marked, but the probability of having that mutation occur in all three pups, is very, very small.
I knew about a chimera labrador which belonged to a geneticist at Va Tech. This dog looked like a calico cat – patches of black and patches of yellow. But the testicles were pure for the black lab part and the dog bred like an all black lab when bred to a yellow bitch.
I have had the collie marked pups show up from a breeding of two 60% spotted dogs – this was before the akc dna test – but the parents were only with each other during the appropriate time of the bitch’s season and the breeding was vet supervised AI. However the one parent was much darker than the other and over time I have seen that when you have spotted dogs in a litter the ones who are darker in color were usually have larger spots than the ones that are more dilute.
Breeders claim they have a DNA test that confirms the sire.
Now, let’s assume a different sire. Fine. But mistaking the mother is almost impossible, so she’s either the dam or they’re just liars and if they’re liars this becomes a less interesting question. Question being, what does a mother who is “normal” Irish White, we assume 2 copies, going to pass to her offspring if the sire is not a carrier for Irish White at all. Does ONE copy of Irish White produce any effect?
Or can a dog be a silent carrier of it?
Yes, they can be a silent carrier.
If potential sires are closely related and only one male is tested it is possible for the other dog to be the actual sire. This is because there are relatively few marker loci used in the testing and those loci are not known to be associated with known gene products. When I had a dual litter sired litter sired by 2 half brothers we had to get additional loci in the test as the first run did not distinguish between the sires for two of the 8 puppies. On the other hand one sire was brindle and the other was not and the two ambivalent pups were brindles so I knew anyway. Brindle is a dominant gene.
White MARKINGS (not all white albino and dilute dogs) are due to a deficiency in neural crest cells (NCC)(progenitors of melanocytes) in the embryo. The relatively predictable pattern of white markings, as fewer NC cells are present is because other developing organs have a sort of priority during embryonic development. These include sensory structures in the inner ear, bones of the voice box (larynx), certain bones of the base of the skull, enamel organs of the teeth, adrenal glands and the paired ganglia that run along the spine. It has been difficult to study in detail whether certain types of spotting are controlled by separate genes but there is evidence that the presence of a white blaze in dogs with a fair amount of color (the irish marked or “mantled”) color may have a separate gene that prevents the white blaze.
Extreme white spotted dogs in which there is no color over the ears are frequently deaf due to the inner ear not getting melanocytes either.
Christopher: There are so many mismarks as they use to be called being shown in the Collie ring today and winning with yet another new generation coming forward in our pure breeds. I continue to investigate old breeding protocol. Refusal to address current scientific discovery for future breeding planning teaching the next generation of breeders.So we have history repeating itself but the next generation of breeders are used for the experimentation or knowledge of why it was eliminated pattern not color decades ago. The Collie is a canine and the pattern is known in other breeds TWEED.
Could the answer to these three puppies phenotype be simply that they carry a modifier that is recessive for this coat color pattern of yet another modifier of the Merle gene besides Harlequin? Right people it is not color because these puppies look very healthy but only three puppies in this litter? Does not look like a very healthy litter if only three puppies or these three survived?
I can only speculate which only a pedigree could document in what I determine to be experiments with color patterns not color since there are only FOUR Colors ..black/brown/red/yellow. I was instructing a novice breeder when I brought up your blog. Who ask about these puppies and my knowledge. I told her she should develop her own ethics and carefully study the breed. It is not Coats of Many Colors, but Coats of Many Patters. This is because harlequin modifier of the merle is out there in our bloodlines and its expressions can be troublesome. No data with exception of taking lessons from the Great Dane. Likewise instructing her that the Tweed Pattern is yet an undiscovered marker as far as I know in canines of a speculated modifier of the merle gene.
I also speculate that a pedigree study would reveal experiments into color patterns of harlequin modifier that might well produce a pattern in Collies called TWEED if indeed this sire and dam phenotype reveals the modifiers of yet another MITF/SINE Piebald or white factoring that has undergone a mutation through the MITF/SINE of both piebald and merle gene modifiers. Modifiers can be plus or minus.
I also instructed her that there are other head styles in the conformation ring that breeders call the Coffin head rather than the classic style which might well describe in collies a a block head. There is also a head called a stove pipe …which can be revealed by the third generation without full knowledge mixed incorrectly can end up being so heavy in the third generation.
Yes, it is also possible there were more than one sire. A sire from another breed as suggested. However, it is always been stated “mismarks produce more mismarks” Since the Collie breed is well known in many cases by its pattern markings. Coats of Many Colors …Wrong..Kaleidoscope of Colors …NO. Coats of many patterns the collie is not a separate species. Breeds with the TWEED pattern..Yes, I have seen it done with breeding through AI’s deliberately two sires and tested determining which sire in the Collie produced which puppies from a single litter.
http://www.doggenetics.co.uk/harlequin.html
The Tweed Merle Modifier
.http://www.ashgi.org/home-page/genetics-info/faq/coat-color
http://www.doggenetics.co.uk/harlequin.html
Recent study of Catahoulas has produced a genetic test for this tweed/patchwork pattern. It turned out to be a variation of merle, designated M(a), which usually only shows up when there’s another active merle gene (M or M(a), but not M(c)). M(a) is usually the cause of cryptic merle dogs. M(c) is a version of merle that shows up in genetic testing, but which is truncated to the point that it doesn’t function as merle anymore.
M/M(a), M/M(c), M(a)/M(a), M(a)/M(c), and M(c)/M(c) do not appear to have the same eye and ear issues that M/M dogs have.
I believe they’ve also identified the cause of “herding harlequin,” the pattern of merle where the base coat is so dilute it may even appear white, in breeds without the Great Dane harlequin gene. Again, it is a mutation of merle rather than of harlequin, genetically.
https://www.facebook.com/groups/CatahoulaCoatColorGeneticsPaintingTheCanvas/
http://catahoula-coat-color-genetics.webnode.com/merle/
Both above websites have a wealth of information for anyone interested!
Chris I keep going back and looking at this sire and dam. The sire appears to be a pure for sable since Irish patterning is not a mutation as s^p which like the merle gene is SINE/MITF piebald a recessive…and pure for sable …red…can hide the white which is not the case in the sire. The dam would normally call this spotting the existence of the merle gene in this dark spotting on it’s side? There are Collie breeders today playing with the patterns of days gone by…not only with the harlequin gene but the Tweed pattern? Tweed causes patches of random colours to appear in the merle coat, and can sometimes also cause disruption of tan points so that they seem to “bleed” into the main coat. In some breeds the term “tweed” is sometimes also used to refer to “muddy” merles (ones with dark or heavily ticked backgrounds), but this is not the same as the true tweed modifier, which occurs mostly in Australian Shepherds and Catahoula Leopard Dogs. We know that early imports of Rough Collies were just black/tan and some just black/white like the Border Collie. We see in old books Collies described as tortoise in pigmentation for example. We can even see broken brindle expressions in some of the old photos. Many dog breeders have tried to study the genetics of coat colour in their particular breed and most have relied on Little (1957). In most breeds, a relatively narrow range of colours is allowed within the standard and in a few breeds, all dogs have the same colour pattern. Certain colours have been considered a disqualification in some breeds, because either they were considered to suggest crossbreeding or the colour was considered to have deleterious side effects. In the case of the Rough Collie those breed distinctive markings became part of the standard. Even today after so much scientific evidence on merle to merle breeding this continues in the collie breeder whelping box undeterred. Undeterred by the warning cry of the Great Dane who nearly destroyed their breed with the harlequin modifier of the merle gene …Some Collie breeders continue as if the breed is a separate species not a canine. So what is the next color pattern of the merle gene to be explored for those who are drawn to the unusual? A merle modifier is a gene that, when inherited along with merle, will affect the way the merle pattern appears. Today high number of merles are bred especially sable merles and when they are tri factored inexperienced breeders can get some unpleasant surprises in the whelping box. (more merles increases the possibility of mutation, and merle is known to be a fragile gene that mutates more frequently than most others). Tweed is at this time considered to be a dominant gene just as the harlequin merle modifier.
Because piebald is a recessive gene and heterozygotes (piebald carriers) don’t always have any white markings, it can remain hidden and pop up unexpectedly. The Poodle and the Shar Pei, traditionally solid-coloured breeds, occasionally produce piebald (known as “flowered” in Shar Pei. My mother law bred those miniature poodles and they were Flowered as well Her Hercules was black with white spotting. She bred a White poodle to a grey poodle.
Chris:: Is it not way pass the time that old Coat Color Theories of Little be replaced by Scientific Fact?
I have a neighbor who breed is American Foxhounds and have had an interesting discussions. He had bred a double piebald female Foxhound for her outstanding Temperament and maternal ability to produce offspring with the same qualities sought for pet quality and well as ability to hunt. . Cross breeding his English imports with blazes.
Problem the blaze is yet as far as I know modifier of the piebald gene is yet to be discovered.
He had believed just stubborn in some cases with selective hearing. Open minded of a herding breed breeder listened because while producing great temperament but too frequently offspring that fail as hunting hounds but night blind. Likewise, running into difficulties with food aggression and fighting over food with he was distressed over the scarring of some of his dogs from this fighting. What distressed him that his Vet had never revealed to him that this dog could not obviously hear as pointed out to him the obvious signs she could not hear.
Looking at his breeding pair of last litter was able to enlighten this breeder as to his concerns for not only temperament but functional hunting breed ,food aggression. with developing eye disease issues.
Sharing with this breeder knowledge now existing for all breeds was elated to better plan his next litter. Old Terminology is so misleading in the formation of breed standards that is outdated with new Scientific study technology that all breeds inherited only four colors…black/brown/red/yellow depending on the complex dilution patterns of phenotype expression. Yep all mammals even horses which he better understood owning and breeding horses.
Piebald for example scientific studies are not complete but can produce the identical phenotype coat color expression if present in a litter be it a hound, or herding , terrier etc. Pointing out the white haws of this female double piebald and the other issue of large white haws in offspring that eye disease issues were obvious from my own breed and interesting the Great Dane studies and findings to him.
The same mutations such as blind, and deaf, bone structure, organ mutations etc regardless of breed or species of mammal ..example horses and dogs. Lack of pigmentation of black/brown, red/yellow is poorly understood as the effects of the dilutions just as the mutations with varies name even for blood diseases from my recent studies of this breed to share today’s scientific findings which was present in the rescue he had taken into his kennel.
When it was pointed out this white fox hound actually can not hear …not selective breeding he was questioned. Do you think that a dog which has limited sight or can hear can produce offspring who can see and hear. His reply, “No that makes no sense at all”. “But why did not my Vet who I pay $200.00 at least every time I go in there …not tell me?” Likewise pointing out the white haws of the piebald that he was doubling up on in his breeding has resolved his eye disease issues. .
Is it not time that Old Little Coat Color Theories be replaced in Pure Bred Coat
Standards? My neighbor of Foxhounds was grateful for this knowledge as he stated…” I have to bred for pigmentation realizing the information that the eye is the end of the spinal cord.
I love this wonderful site that keeps up to date very well with all new findings. http://doggenetics.co.uk/white.htm#series. I do agree it could result of genetic chimera. Breeding protocol of the Collie with again Merle gene and lethal dominant modifier of Harlequin likewise seen the Calico collie. This also could be a reversion and will not produce their phenotype but their genotype?
Replied in the wrong spot, sorry.
Both parents are some kind of Collies and not random mutts, and grandparents have white too I assume? If yes, then wrong sire.
Knowing the ethical color headed white breeder of collies of by gone days.. Surprise first headed whites after 50 years in the breed. Breeding protocol must consider the knowledge known and speculated by science. We have much yet to learn and discover about the white spotting in dogs. I agree mutations continue to be created with fashion and fad breeding.
Kathy Bittorf: Mutations cannot be “created” with fashion and fad breeding…whatever that is.
Christopher the mystery of white expression puzzled good colored headed white breeders before the “white” fashion fad once again has raised it’s ugly head. The sire and dam phenotype does not reflect to me either is carrying two recessive genes for piebald. The white does not come over their hocks.
Even if both were genetically White tested and came back both parents were s^p/s^i …it does not explain the phenotype of these puppies. It is possible that the genotype of piebald is hidden and they could test carrying the piebald (white factoring).
The white spotting specifically in Collies is extremely complex. Example: Two parents sable white factored produced 10 puppies. Three were tri factored sable headed whites, one puppy had no white markings whatsoever. Only one puppy sable phenotype white factored. Others no full white collars. Modifiers . Pure for sable can hide white genotype could be another reason. However, the dam appears to be tri factored? .We know at one time there were black/white and black and tan collies when the breed actually apparently had a dominant black gene in gene pool much like the Border Collie. The dam’s color pattern?????
The white spotting in canines is complex. Breeds: Collie, Great Dane, Italian Greyhound, Shetland Sheepdog, Boxer and Bull Terrier, piebald or old term “white factor” manifest as a dosage-dependent trait. Piebald is now identified by a marker MITF. A dog with one copy of the MITF variant has some white pattern expression, while a dog with 2 copies of the variant display more extreme white with color only on the head and perhaps a body spot. “In Boxers and Bull Terriers, dogs with 2 copies of the MITF variant are completely white and dogs with 1 copy display the mantle (called flash in these breeds) pattern.” These breed seem to have additional mutations in the MITF or there is likely other genes for white spotting in these breeds. Piebald is stated to be a recessive trait taking two copies to produce the white patterns or spotting. Old hypothesis was plus and minus modifiers.
My guess regardless is these two puppies phenotype likely is not their genotype. It would be fantastic if the old dominant black was back in the gene pool.
Bottom line modifiers of the piebald gene likely are the answer yet to be discovered. Old term white factoring but like the merle gene piebald (s^p) SINE/MITF. Irish patterning is said to be present in all collies today. Well don’t see irish patterning here?
Kathy Bittorf: Those puppies do not look like dominant black to me. Difficult to tell from the photo but one if not all looks tanpoint.
Chris I have the puppy with no white markings born May, 2016 with three sibling brothers that are sable headed whites.
Those puppies are so dark colored and their parents so relatively light colored, that I would also speculate a different sire. In my limited experience Ay sables are born as light as they will ever be and then darken over time.
Both parents might be tri-factored, even if the sire isn’t expressing it at all, and the middle puppy might conceivably be a tricolor: the lighting is so poor it is hard to tell. However the two other puppies are definitely sables and that much black shading is slightly unusual on small puppies. They will probably be very dark colored dogs someday.
As Kathy said said, spotting of almost any kind can definitely be carried as a recessive and spotting is a very complicated and poorly-understood subject. Little’s old simple theory of irish spotting was thrown out a long time ago, even if it does work most of the time. I certainly wouldn’t lynch any breeder over it before a paternity test was conducted.
Truthfully Ay sables change a lot over time in general and I wouldn’t lynch any breeder over that either.
The main reason I suck at coat color genetics is that, like you, I really don’t care so long as it’s not linked to health issues.
But I’ll follow this. It almost seems like something one is COMPELLED to learn.
Because widening gene pool often involves questioning why some colors and patterns are “incorrect” in some circles, when they have no health issues connected. It’s just ridiculous.
I’m also going with “sire is not who they think he is.”
Coat color genetics are actually pretty interesting, plus it’s a good entree in to more complex/essential genetics. It’s not just about “how can I get that color,” IMO.
I don’t have any answers, and am certainly not a color guru 😉 but this came up on my FB memories, and I thought it might be of interest in the discussion:
https://www.sciencedaily.com/releases/2014/07/140714100122.htm
link doesn’t show thumbnail, it is an article on the theory that mild neural crest deficits are responsible for some of the traits related to domestication, including white patches. So perhaps, somehow, these pups don’t have this deficit, in spite of having parents who do. Our current color theories would seem inadequate to produce this result, so some kind of epistasis might be implicated.
Perhaps the parents aren’t actual Irish spotting (homozygous recessive) but “pseudo” Irish spotting (Heterozygous for dominant “no white” & recessive “piebald”).
This way puppies can be produced that are homozygous for no-white.
Richard I totally agree with your speculation. Rather than Little’s theory of the S locus like K Mortensen states been put in old theory that could not be supported scientifically ….Believe in 2006 maybe 2009 through scientific study and discovery of the s^p piebald gene. This gene like the merle gene is SINE at the MITF gene.
The term Irish spotting pattern has been tested by markers in dogs that are S/sp heterozygotes.
I am inclined to support postulations since a marker for “Irish Patterning “has yet to be found that there are plus and minus modifiers of the MITF-M or MITF + M
There may be other genes, besides MITF, involved in spotting, but further research is needed to determine.
Irish spotting pattern occurs in dogs that are S/sp heterozygote. Therefore if both sire and dam were S/sp
http://jhered.oxfordjournals.org/content/100/suppl_1/S66.full
Is it possible that the parents were piebald carriers, not true irish spotted, and the puppies by chance all inherited the solid gene from both parents rather than the piebald gene?
Or are collies, like border collies, meant to be homozygous for irish spotting? If so I can’t see how they acquired the solid genes.
I know I’ve seen sable rough collies with no white markings before so this isn’t a once off occurrence. I wish I’d asked the owners if the dogs were purebred or mixes now :p
As a side note: I have a BC / shepherd crossbreed that is black and tan (with black mask and black shading on the legs and chest) with a white paw and a white star on the chest – so can attest that 1 copy of irish spotting produces little to no white (same amount of white can apparently be produced with no white genes at all as a result of imperfect colour migration across the embryo – which is why occasionally labradors can come with tiny spots of white in these areas).
So? What’s the catch? Dog people pay far too much attention to color and this case doesn’t look like it has any health implications . . .
Jennifer I don’t the catch here. Do we take lessons from the Great Dane studies and findings and warnings from the Great Dane breeders? Or do we continue to accept that the coat colors are only four colors black/brown, yellow/red in the canine species? All differences in phenotype expression is based on Color Patterns not pigmentation of phenotype.
Those pets are so lovely. Oh, I’m so jealous!
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I have seen many instances of those too. But I echo Jennifer’s comments.
Queenie every time we have produced such a small litter something is terribly wrong.
For all intents and purposes, phentotypically it appears that these are mixed breed puppies physically speaking as well as color. Another dog apparently bred the bitch, but a DNA test could confirm this. Interesting discussion.
The puppies are definitely not Collie puppies. Collies have the so-called Irish pattern or markings consisting typically of the white collar, legs/feet… I agree that this situation should require a DNA test.
Note: I just finished reviewing an article about “Pseudo-Piebald.” More food for thought…
I once saw a ghost merle border collie in Idaho. Beautiful dog. Nothing to do with white scruff markings, but genetic variations like that are fascinating. Not sure how the ghost merle happens.
Just to be clear, it wasn’t a cryptic merle, or a white double merle, it was an actual ghost merle, it had the merling pattern very faintly over its body and was a silvery color. Owner told me it is extremely rare
Easy. If the gene is dominant, and both parents are heterozygous, it’s entirely possible for all three pups to inherit an inactive allele from both parents. Rare, but quite possible. Xx to Xx 25% XX 50% Xx 25% xx This would be a litter of three xx’s.
In horses, it has been found that what were once thought to be single genes (Dominant White) are actually many different alleles (there are now 20 known “Dominant Whites”!) I would speculate that this may be a similar case. The parents look Irish-spotted, but it may be a different allele that produces a similar appearance while being dominant or incomplete dominant.
The puppies are definitely not Collie puppies. Collies have the so-called Irish pattern or markings consisting typically of the white collar, legs/feet… I agree that this situation should require a DNA test.