NOTE THE INCLUSION OF THIS ARTICLE AT INDIVIDUAL BREEDER WEBSITES IS UNAUTHORIZED & THE DISCUSSION OF COLOR & MARKINGS BELOW NO WAY SUGGESTS A SUPPORT OF INDIVIDUAL BREEDER PRACTICES OUTSIDE OF BREED TRADITION.. ALL THOSE WISHING TO PURCHASE A GREAT DANE IN THE USA SHOULD BEGIN BY VISITING THE GREAT DANE CLUB OF AMERICA'S WEBSITE.
**NOTE: The articles in the section on "Great Dane SPECIFIC Coat Color Information" are intended specifically as a practical aid to those breeding & exhibiting Great Danes. They may not always be relevant to other breeds & the information is deliberately not technically minded.
MANTLE DANES: GENOTYPE & PHENOTYPE
GENOTYPE: MANTLE DANES can come in one of two basic genotypes. They are either irish homozygotes or piebald heterozygotes. Irish homozygotes will "breed true" (as the expression goes) for the Mantle pattern, because these dogs have two copies of the gene that produces what is traditionally called "Irish markings" that we associated with white trim (tuxedo markings). This genetic pattern unfortunately does not completely match up with the current written AKC standard for the Mantle Dane, but does follow the general tradition for "harlequin black" that is preserved in the FCI standard (with the exclusion of the recently added Plattenhund). In other words, Irish pattern produces a partial-collared to full-collared sort of Mantle dog, a dog that will always have white on the muzzle, have socks or stockings, belly and/or chest white, and a dog that will never have a break in the blanket, or in any way have the white "creeping into" the body markings. This is the true Irish dog under CC Little's old system. The piebald heterozygote is CC Little's "pseudo-Irish" dog. This dog will have a much wider variation in markings anything from mismarked black to broken-blanketed Mantles (near piebalds) are possible in the heterozygote due to the erratic nature of the piebald gene, more formally known as MITF SINE mutation, also called excessive white or random white. Both genotypes (true Irish & pseudo-Irish) produce the Mantle phenotype. Both produce iterations of acceptable (show) markings. But the key here is they will breed very differently. That hasn't been well understood to date by most Dane breeders.
Another difference here from what most breeders were taught, and is newly discovered, is that the Irish pattern we find in our dogs does NOT appear to be produced by the same gene that produces piebald (Der Plattenhund). Piebald turns out to be the simple (& single!) recessive at the "S" locus. The dominant homozygote is a solid black (self-colored) dog: <SS>. The recessive homozygote is a piebald--Der Plattenhund: <s^p/s^p>. The hybrid that results from a dog being heterozygote here is a recognizable sort of Mantle typically--but is Little's "pseudo-Irish" dog: <Ss^p>, a "hybrid" produced by two genes that won't otherwise give you a Mantle, so these "pseuo-Irish" Mantles will breed differently from the "true" (homozyous) Irish dog.
Now it is the case, in introducing the piebald gene into various gene combinations, some of the resulting hybrid (heterozygote) puppies can range from what some might called "mismarked" black or mantle to Mantles with a broken blanket. This range depends partially on other factors unrelated to the S locus (mostly if the dogs in question carry Irish genes as well), but also results from the piebald gene simply being unstable. Typically in a litter where piebald is present you WILL get a wide, wide range of markings: from nearly solid puppies to nearly white puppies. This is because the piebald hybrid parents set of genes that make them appear as Mantle-marked split in the offspring, recreating the black-to-piebald range their parents came from. Any animal with white markings on the body proper (torso), all Mantles with breaks in the blanket will carry the piebald gene (i.e. are pseudo-Irish Mantles). Although Piebald Mantles can have very flashy Mantle markings at times (white blazes, high stockings & wide collars), they also tend to have and/or throw pups with peculiar head markings (nearly lacking in white or predominantly white for example), & with very assymetrical markings (full collar on one side, but mostly lacking collar on other side--high white stocking on one leg, short white sock on another, etc.). These are visual clues, but to be sure of a dog's genotype it's best to test, & there _is_ a gene test for piebald (see the GDCA website, H&W section for a link to all coat color gene tests).
In contrast, if the breeder concentrates on producing Mantles who are Irish homozygotes, the range of markings is going to be much narrower & more stable &more symmetrical in pattern: all the puppies can be expected to have some kind of recognizable Mantle markings: white on their extremities (legs, tail, muzzle), and all the puppies will have solid blankets and good head markings. In other words, Irish homozygotes breed true & the resulting litters will have puppies who only range from having partial collars to full collars. No solid (or mismarked) blacks or piebalds will be born to matings where both parents are Irish homozygotes and free of the piebald gene. The Irish allele (gene) is NOT on the same locus (gene location) at piebald; it is NOT at the S locus as was once thought, but on another chromosome entirely, so this means this gene sorts independently--i.e. it is inherited seperately from piebald and as a distinct trait a breeder can focus on concentrating in their bloodline. Very little in Harlequin breeding offers this sort of control, so it's a valuable point of pattern managment to be able to establish homozygosity of this gene. Here a dog can have one, none, or TWO of the gene. Those dogs with zero Irish genes will be solid black, those with one mostly will appear as mismarked blacks (in the absence of the piebald gene); those with two will always display a Mantle pattern.
Although many pseudo-Irish Mantles lack Irish genes entirely (because these recessive white genes are cumulative, meaning they all add white markings to the dog, so then the dogs become too white to be called true Mantles at some point), there are some dogs will have one copy of the Irish gene as well as one copy of the piebald gene and appear as flashy Mantles. And there are some dogs without anything but one copy of the piebald gene that can end up being defined as mismarked Black/Mantle. This gene is just very unstable in the markings it produces. Piebald heterozygote Mantles will typically have flashier markings than their Irish Mantle counterparts, but the markings will also tend to have certain tell-tale traits: (1) a break in the blanket is a dead give-away the Mantle is a piebald hybrid, not a true Irish Mantle, (2) asymmetrical markings are a characteristic of the piebald gene, and in contrast the Irish gene produces stable, symmetical markings--so dogs with socks on one side, high stockings on the other, dogs with odd & assymetrical markings are likely piebald hybrids, (3) creeping white into the body proper is a trait of piebaldism; this is the attempt of this gene to break the body up into the spots, or "plates" of color that are characteristic of this gene in its fully realized form, and (4) broad blazes & blazes that extend into the collar are typical of piebald hybrid Mantles. So dogs where there is a strong line in the flank creeping upward, where the collar becomes a large shawl, where the blanket (mantle) on the body doesn't reach down toward the belly, where the head markings are completely split into two black areas over eyes/ears (i.e. the "cap" is lost), are all traits characteristic of the piebald gene.
Although there isn't yet a test for the Irish gene, a show marked Mantle dog that tests negative for the piebald gene can be pressumed to be homozygous ("pure" or "true" Irish). Note all AKC show-marked Harlequins (as well as the mantle-marked merles) also must be pseudo-Irish or true Irish as to genotype. Especially with Harlequin only by gene testing can genotype be firmly defined. The value in testing where a question exist is to avoid breeding two piebald carriers to each other (at least unknowingly) because the result will be a loss of show marks & the potential for increased problems with deafness also exists, simply because dogs predominately white, for whatever reason, are at risk for hearing loss.
THERE IS A TEST FOR PIEBALD (CALLED EXCESSIVE WHITE) COMMERCIALLY AVAILABLE: SEE HEALTH GENE
A TEST FOR IRISH SPOTTING IS CURRENTLY PENDING COMPLETION OF ONGOING RESEARCH.
Also it is important to understand that SOME, but not all, Mantles carry the harl gene sight unseen. This is now established fact & can be tested for. Those Mantles that carry the harl gene can produce a higher percentage of Harlequins than the Mantles that do not have the harl gene. No Mantle (no living dog) has two copies of the harl gene. So the choices are one or none. This has two consequences: (1) no dog can breed true for the harl gene, and (2) Mantles & Harl-bred Blacks, as individuals, contribute "unevenly" to the production of Harlequins, with some unable to offer any "help" to the increase in the percentage of harls in a litter (those without the harl gene), while others can statistically increase the percentage of harls in a litter from a harl x mantle breeding, but actually produce harlequins from a merle x mantle breeding. A Mantle MUST be bred to a dog that is merle-bearing to produce Harlequin puppies. No Mantle x Mantle breeding can ever achieve this. This is information directly from the geneticist who discovered both the harl & merle genes. See her list of publication at her page at Clemson: Dr. Leigh Anne Clark. JPY-2010.
THERE ARE TESTS AVAIABLE FOR BOTH MERLE & HARL GENES: VISIT THE GDCA H&W PAGE
|PHENOTYPE: Two early articles from the 1990s are reproduced below. You will need to scroll down to see
second article. There are also some illustrations, photos and links to other material relevant to the Mantle Dane
below. To see the parent club's Illustrated Standard, click here.
To see the latest genetic information on coat color, click here. The
illustration on the right is the range of Mantle as to pattern if you simply equate each Harlequin illustration
individually. It is NOT "official" but does correspond to the standard as pertains to the breeding partner
to the Harlequin, which is what the Mantle is intended to be (the current AKC standard is arguably too "white"
to correspond properly to the traditional phenotype, as well as the most appropriate genotype, of the Mantle).
Were one to use a standard that matches that of Harlequins (both genetically and phenotypically--which really should be to be logical?), here are two examples borrowed from other breeds of how it could read:
Mantle - The color shall be black and white with a solid black blanket extending over the entire body, black skull and black ears. White markings must be always be present and can include: a full or partial white muzzle, with or without a white blaze; white socks or stockings; a white chest; white tipped tail; a whole or broken white collar. White should never predominate on the head or the body. Specimens over 30% white must be disqualified.
Mantle - Base color shall be black with white markings. A solid black blanket should extend over the entire body and the eyes and ears should be fully surrounded by a "cap" of black. White markings should always be present and can include: white socks or stockings, a white muzzle with or without a white blaze, a white chest, white-tipped tail and a white collar, broken or whole. White marking should never extend so far onto the body as to be found above the flanks, and any break in the blanket should be penalized. White should never predominate on the head or body. Specimens more than 30% white should be so severely penalized as to effectively elimidate them from competition.
|THE RANGE OF MANTLE to the right is what parallels the current AKC standard for the Harlequin: note still
the "less acceptable" Mantle at the bottom does carry for piebald, as could also the "less acceptable"
Mantle that is very heavily marked.
There various approaches (both currently and historically) to how to deal with white on black Danes. Here are a couple of current examples arguably relevant to AKC debates:
HERE IS THE CANADIAN STANDARD: Boston or Black-Mantled Danes:
A black and white dog with a black mantle extending over the body; white blaze or muzzle or both; white chest; white on part or whole of forelegs and hindlegs; part or whole white collar; white tipped tail; dark eyes; dark nose. Acceptable but less desirable - lack of collar.
Faults: Any variation detracting from the general appearance.
HERE IS THE FCI STANDARD: Black Jet black, white markings permitted. Included here are "Manteltiger" in which the black covers the body like a coat ("mantel") or blanket and muzzle, throat, chest, belly, legs and tip of tail may be white. Also dogs with basic white colour and large black patches so called ("Plattenhunde"). Note that Plattenhunde are a recent and hotly debated item, whereas the "black and white" Dane exists in all of Europe (as a relevant breed prospect) and other FCI countries since time immemorial.
*If merles were ever to be incorportated into the standard, logically this same range of white on them would be asked for, so an accepted standard for Mantle could be adapted to include them--i.e. "mantled merles." jpY
TO See Diagrams & Descriptions of Various Harlequin Family Dogs (including Mantles & Piebalds), CLICK HERE.
NOTE THE BELOW IS SIMPLY OFFERED AS HISTORICAL PUBLICATION: Above the latest, best data:
PHENOTYPE IS NOT GENOTYPE: or why the irish gene is not the mantle gene (1999).
The whole point to understanding Mantledane genetics is that we "straddle" TWO genes (si & sp) by asking for a whole & complete collar as the ideal pattern, while penalizing the other iterations of both piebald & irish patterning. Both genes (alleles) could be in the breed & if one is too often missing it is the irish NOT the piebald.
If we had allowed the Mantledane, like the Collie or Boxer, to have white up to and including 1/3 (but no more), we would have been selecting for the irish allele. Had we asked for at least 30% white & allowed up to nearly all white, we would have selected for the piebald allele. As it is, we wrote the standard to select for a PHENOTYPE, not a genotype, so we end up with a large variety of genotypes that fit that one phenotype. Which means that all those pretty marked Mantles may have very different genes, meaning dogs who look alike won't throw alike, so predicting pups from the parents (as to color) has some problems. Here are some examples of genotypes that could create the ideal mantledane pattern & it's allowable range by the illustrated standard:
1) Ssp & Sse--both are the so-called "pseudo-irish" that are created by a breed, like Cocker Spaniels that allows for solids & piebalds. This is thought by many to be what creates a flashy Boxer (not the irish gene) & obviously represents two genes the Great Dane DOES carry (as solids-fawn, blue, brindle, black, must be SS & harl families commonly exhibit the spsp pattern.) These dogs, when bred to each other, often have solids & very white dogs as well as more irish patterned offspring. The range of pattern shows it is a hybrid. No more than these two genes need be in Danes to explain everything from solid fawns to boston-headed dogs, & all possible white & solid pattern combinations in between, but what exact recessives & in what percentage are in the breed is currently unknown. To see how Mantles, piebalds & solid Danes can be related, click here.
2) sisi--"true"(homozygous) irish--most irish dogs, however DO NOT have a collar, only throat & belly white, that is they are NOT "collared" mantles, but so-called mismarked blacks (when you are talking about the Dane). Look at the Collie as an example. Irish is NOT the "collar" gene, it codes for "white trim, but less that 1/3 white total." Many mismark blacks are "pure" irish. Breeds who 'depend' on the irish gene, like Bernese Mountanin Dogs NEVER demand a full collar, but they do penalizes excessive white. It is only speculation that breeds like the Basenji carry exclusively for irish (to make a collar) & that speculation is based merely on the idea of the pattern in such breeds being so consistently symmetrical, which is not normally thought to be a characteristic of the piebald gene. There is no current, ongoing work for these recessive white spotting genes, so there is little factual evidence to base opinion on where they are concerned. However all "irish" dogs can and do consistently produce a dog with white trim in a "tuxedo" pattern and this form of a recessive white is never associated with defects and actually forms the "undercoat," the phenotypic base, of the normal Harlequin.
3) spsp-the piebald Mantle--also "pure" or homozygous--this is the flashy boston who typically "drinks his blaze" (with a split head blaze & full & complete collar from the backs of his ears to his shoulder blades). These dogs will likely have breaks in the blanket (as may, BTW, dogs with only one piebald gene!). Dogs with extensive, flashy white markings, where the black on the head is only around the eyes & ears, with full white collars, and dogs with breaks in their black blanket carry the piebald gene, as the irish gene cannot extend it's production of white this far from what we understand. A piebald (sp or maybe se also called sw) gene is also then likely present when you have assymetrically marked dogs, such as split headed dog-with one side of the head black & the other white, as well as those dogs with white socks on one side & high white stockings on the other. This is the gene that Brittanys, for example, carry. The markings are less symmetrical than with the Irish gene.To see the piebald-in-action in the Great Dane, click here.
4) sise/sisp--the hybrid Mantle--this, like the "pseudo-irish" give the appearance of a mantle, but the genes here, again, are different, so the dog does not consistently breed the pattern it carries. These animals produce many very white (lightly marked) harls & dogs lacking body color. Such dogs CAN produce mantle-headed or even nearly completely white dogs who do NOT carry the merle gene. It is even possible that sese Dane pups could be deaf whites with blue eyes. These animals would NOT be (white-double-MM) merles or harls; they would have the same basic genetics as the Dalmation or Bull Terrier & have the same reason for going deaf.
The take home message is two-fold: #1. there are several possibilities for genotypes that will appear as a "perfect boston," but they will breed very differently, as the one phenotype can be made by a variety of gene combinations & #2. breeding flashy animals (harls or mantles) will increase your chances of getting deaf pups. Again, to avoid problems (& a lot of study!), simply use the illustrated standard as your guide & avoid the use of mismarks if proper pattern is your goal. The article published in the Great Dane Reporter (stud issue 1997) not only gives the details of Mantledane Genetics (its title),but also illustrated the range each type of mantledane can produce from its "hidden" genotype.
This message prepared by JP YOUSHA (1998) for educational purposes & permission is given to disseminate this message for that purpose & that purpose only. All copyrights & authors' rights are to be respected. For further information contact: email@example.com
MANTLEDANE GENETICS: How to get & keep Boston-patterned dogs.
By JP Yousha (1997) GDR.
As the "6th class" has now been approved by the GDCA, and mantle danes will soon grace the conformation ring in the U.S.A., a discussion of the genetics involved in acquiring and maintaining the pattern Harlequin breeders have traditionally referred to as the "Boston" would seem in order. Although approval of what exactly constitutes the correct markings for the mantle dane has yet to be fully articulated and approved, Harl breeders have a general idea of wht describes the boston-patterned Dane. This description ideally refers to a black and white dog with a coat, or mantle, of black that extends over the topline from the withers to the croup, with four white stockings, a full white collar, white belly and tail tip, and generally a white blaze on the head--with black fully covering both eyes and both ears. This pattern is seen in a variety of other breeds besides the Great Dane, and many base colors (e.g. fawn, brindle, blue) can coexist with this pattern. The pattern is a result of the action of genes (alleles) present at the so called "recessive white" or "spotting" series (S Locus). In dogs, this series has four basic variations (alleles) that produce a range from a solid or "self-colored" dog through varying amounts of white spotting to an all white dog (see illustration). Each of the four genes (alleles) in this series produces a range of white on the dog rather than a specific amount of white. And, although the first lesson of genetics revolves around Mendel's Laws, which state that genes sort independently, acting more like different colored marbles combining in dominant recessive pairs, than like paints mixing on a palette, there are exceptions, and the recessive white series is one of them. This gene demonstrates incomplete dominance, so that the "painterly effect" does occur when two genes combine. The classis example of incomplete dominance in genetics is the four-o'clock flower, in which cross-breeding two true breeding (homozygotic) red and white strains does result in pink flowers, rather than the expected dominant red flowers in the first generation, with the recessive white showing up in the second generation.
The recessive white series (S Locus) is further complicated by "modifier genes" which act on the main gene to increase or decrease the amount of white present in individual dogs. The main gene only allows a certain amount of variation in the amount of white; however the modifiers' effect results in both individual dogs with the same main gene having a somewhat different appearance, as well as an overlap in the apperance of dogs carrying different combinations of genes of the four main genes (alleles) in the recessive white gene series. For example, dogs who carry only the solid or "self" gene of the recessive white series can vary, due to the actions of modifiers, from completely colored to having white on the feet, chest and/or belly. Fawn, brindle, blue & black Danes typically have this pattern and carry only "self" genes. When breeding these dogs, if white is present at all it will be confined to these specific areas; you won't see dogs with blazes and collars, but you cannot always get a completely colored dog every time, due to the action of modifiers.
The next gene in this series produces a range from what Dane breeders refer to as a "mismarked black" to a full collared boston at its extreme range. Many breeds carry two of these genes (alleles) commonly; typical examples are seen in Collies, Basenjis and Boxers. In these breeds, generally no more than 1/3 white is allowed, and this 1/3 white represents the most white this gene (allele) can produce with a full extension of modifiers. These breeds typically allow less white to be present, and this reflects the general action of this gene, which produces white feet, belly/chest and/or throat commonly, with or without a broken (partial) or full white collar. Again, you can breed for the general pattern of "no more than 1/3 white," but it is unlikely that all individual dogs will carry the correct modifiers to produce only offspring who hve the full extenson of white that results in a full collar. This gene is referred to as the "Irish" gene (allele), and generally produces a more symmetrical pattern than the piebald gene described below. There is some dispute over whether this Irish gene is present in the Great Dane: the patterns commonly produced by this gene can also be produced by the piebald gene or the combitiona of the piebald and solid genes.
The next gene in this series is referred to as the piebald gene. This is the gene traditionally believed to be commonly carried by the majority of Harlequins. This gene is also seen in spaniels, pointers and Beagles, and it produces a range of white from partial collared dogs through a variety of spotting patterns to dogs predominately white with only head and tail-root color. Breeds which focus on this gene describe the pattern generally as parti-colored or simply piebald, and do not specify the exact amount or location of white required. Modifiers alter just how much white each dog will have and therefore there will be varying amounts of white in the offspring of piebald dogs. For Harl breeders this range includes "mismarked" blacks & bostons all the way to "boston/merle/harl-heads," in which the dog lacks all body color. The main gene itself, without the extreme action of modifiers, would theoretically produce a dog Harl breeders would recognize as a boston, but restriction of modifiers leads to a "mismark," while extension of modifiers leads to a dog predominantly white. The last gene in this series is referred to as "extreme-white piebald." These dogs are commonly white, with any color present being confined to the head and/or tail root. Sealyham Terriers, Bichon Frise, and Pyrenese carry this gene and display the typical pattern this gene produces. This is the gene that produces the white Boxer and the (non-merle) white Collie that is occassionally seen. It is possible that this gene is carried in the Harlequin family of Danes, and if so, it may be responsible for some of the dogs born who lack body color.
As you can see, there is an overlap in the ranges of white produced by these varying genes in the recessive white series: the solid gene with full extension of modifiers overlaps the Irish and piebald genes with full restriction of modifiers. The piebald gene overlaps the entire series of the Irish gene and is only typically distinguishable as producing generally more white in the offspring with less symmetry of pattern. The piebald gene, at full extension, also overlaps the extreme-white piebald at full restriction (see illustration). There are therefore, several different ways to get the mantle dane pattern (i.e. different genotypes that produce one phenotype). A mantle dane could be a "pseudo-Irish" mantle, carrying one self and one piebald or extreme piebald gene which combine to give a full collar. A mantle dane could carry two piebald genes wth restriction modifiers. A mantle dane could carry two Irish genes with full extention of modifiers (assuming this gene is present in the Great Dane). A mantle dane could also result from the combination of one Irish and one piebald or extreme piebald (assuming the latter is carried by the breed). Of these six (6) possible genetic types (genotypes) of mantle dane, only two are pure breeding (homozygotes), while the other four are hybrids (heterozygotes). When it is possible breeders naturally prefer pure-breeding dogs to hybrids to be able to consistently fix a certain type,in this case a certain pattern, through several generations. Of course, it has already been noted, that when dealing with the recessive white series, an exact amount of white cannot be predicted; control can only be achieved within a range of a specific gene in the series. Although all these dogs would basically look alike (i.e. meet the mantle dane standard), their underlying genetics are different and will result in varying percentages of acceptably marked offspring and distinct types of mismarked offspring. The clues to which "genetic kind" of mantle dane an individual dog is can be found by studying its pedigree and knowing the color patterns of its siblings. This underlying "boston" pattern, of course, affects where the patches will be on Harlequin offspring as well. For example, an underlying full collared boston pattern will ensure the "pure white neck preferred" by the standard. An underlying pattern that is "mismark black" will allow patches to form on the neck of Harlequin offspring. An underlying pattern in which modifiers do not allow body color to form will result in (disqualifying) "harl-headed dogs; Harlequins without any body patches.
If a dog is a pseudo-Irish boston (Ss), he will most likely have solid colored danes clearly in his pedigree. His siblings were likely very close to solid, or appeared as ("flashy") piebalds and bostons. His offspring will generally have the same split: a few near solid pups and the rest with flashy markings. It is possible in the first generation to get full-collared bostons breeding undermarked (harl-head) to overmarked (mismark black) dogs by making a king of (Ss) pseudo-Irish type of boston, however the under & over marked animals will reappear in the succeeding generations, increasing the number of disqualifying mismarks in the litter. In the other types (ss) of hybrid bostons, there will be few, if any, near-black animals in the pedigree and among the siblings. The offspring of these hybrids will tend to have a lot of white on them (when bred to one another), with "true" piebald, predominately white and near-white animals occuring, as well as some boston patterned dogs present. If such is bred to a pseudo-Irish boston, the offspring in the first generation will appear like the pseudo-Irish (i.e.boston), but more & more white will show up in succeeding generations, as the recessive white patterns recombine. Most of the offspring of all these breedings will also be hybrids; the occassional true-breeding solid (SS) may be obvious, but any true-breeding Irish and/or piebald bostons may look very similar to their hybrid siblings.
A true-breeding piebald boston has two genes for piebald and modifiers that restrict the amount of white present. This dog will have a pedigree of black and white dogs with distinct white markings. There will likely be a wide variation in the white markings, both in amount and location. There are probably individuals present in the pedigree with distinctly asymmetrical markings. The offspring of piebald boston matings will show the same pattern; no individual dog will be without distinct white markings and there will likely be a wide range of how much and where the markings occur. Piebald to pseudo-Irish boston will produce offspring that can range from near black to near white. Piebald boston bred to the other hybrids will produce distinctly black and white animals, and near white animals will occur occassionally. (Of course these offspring of hybrids will also generally be hybrids themselves.) A true-breeding Irish boston has two genes for the Irish pattern and modifiers that extend the amount of white present. This dog will have a pedigree with "mismark" and near-black dogs, with no more than the 1/3 white that is typical of the Irish pattern. There should be a distinct symmetry to the white markings present. The offspring of Irish bostons will show the same pattern, with no pups having more white than is found in the ideal boston, and most pups having less than a full collar (with some totally lacking a collar). Irish bred to pseudo-Irish boston will produce very similarly to an Irish breeding, however there may be occassional pup who is much more white or more black than his parents and all the resulting pups will be hybrids and carrying for more white than shown on their parents. Irish bred to piebald boston will also produce Irish patterned hybrid offspring, with likely more white than the Irish parent shows.
To produce full collared Mantles and Harlequins with the preferred white neck consistently through several succeeding generations, it would be wise to breed only from correctly marked specimens (i.e. show marked dogs). Breeding other "off-color" patterns may result in the introduction of hybrids, modifiers and recessive genes difficult to control in succeeding generations. As there are several different genetic possibilities for what is described as a boston, the underlying genes involved are currently difficult to determine. However offspring who receive the boston pattern are the best candidates for a future breeding program. Breeding animals with disqualifying faults, such as "mismarked blacks" and "boston-heads" may very well combine in the first generation to produce some animals with the boston pattern, but these animals will be hybrids from mismarks and therefore be unlikely to reproduce themselves, as the desired combination of genes will be lost in succeeding generations. There will always be a higher percentage of mismark offspring when breeding from such hybrid stock. If only full collared Mantles and Harlequins with the preferred white neck were to be used in a breeding program, it might be possible, by concentrating on acquiring pure-breeding stock, to somewhat "fix" the range of the recessive white gene in question. Certainly a breeding program for harlequin and mantle danes needs to concentrate on breeding animals who fall within the standard. This concentration on breeding only correctly marked animals will result in the highest possible percentage of correctly marked offspring over time. Naturally all dogs used in a breeding program should conform closely to the standard of the breed in all other ways; inferior dogs having the correct pattern should not be used. The genetics involved in producing a mantle dane may seem complex when compared to that of the solid varieties of the Great Dane, but producing correctly marked mantle danes and avoiding dogs who produce predominantely mismarks will still be easier than that of making their Harlequin siblings; a challenge, indeed, to which any competant harl breed can attest!