THE HARLEQUIN FAMILY OF DOGS: Harls, Merles, Blacks, Whites & More
There
always seems to be alot of confusion & "mythos" about harlequins, harlequin breedings & the merles that are born to harls. This little article is intended to answer the basic
questions that most newcomers to the breed have, & to hopefully help clear
up the confusion that comes from conflicting reports about harls,
merles & their family. There is a little more technical information at the
end of the article for those interested, as well as a list of references for
those wanting to study the topic. If you don't want to wade thru all this, then remember, you cannot go wrong if you stick to the
standard & breed ONLY show-marked & breed-quality Harlequins &
Mantles to each other. That's why the standard was written in the first place;
to act as a guide to breeders. So you don't need to understand all these
details & theories of the genetics of coat color,
but you do then need to stick to the standard when breeding. If there is
anything you feel that needs to be added, etc. to this article, please email me & I'll do my best to see your question gets addressed.
First off, the basics
of what you get when you breed. A note prior to presenting
the data & links. Statistically the data are conclusive. This does
not mean you will see these exact ratios of pups in litters,
as such ratios only appear when large numbers are studied. This has been done.
The data are extensive & it's well known what to expect from certain breedings. There is no real mystery to breeding harlequins;
it's not "a crap shoot," & it doesn't require the use of mismarked dogs or weird combinations to be successful.
There is NO secret recipe involving merles or other mismarked
dogs. All this has been done time & again, so PLEASE don't think there is
ANY need to try out odd combinations to "see what you get" or prove
some elusive point. This is simply not an ethical approach to breeding: you do
not care for the breed by "reinventing the wheel" and having litters
to learn what has already been discovered, seen & written about. At the end
of this article is presented an argument about theories of the harlequin
variant. That does NOT mean that the basics are not understood, nor do these
arguments have much to do with the practicalities of breeding harlequins. Read
before you breed, please, and follow the standard when you do breed. A long
list of references is offered at the end of this article & live links are
offered thru-out to help you find the relevant articles & information you
need. If you want to see the ratios of expected pups from various harl-family breedings, read Jane Chopson's article which gives all the offspring
expected from various pairings or read one of the articles I've written, either
the basic article or the more technical one. Louise Feddema
also has one that outlines what to expect from certain
breedings. I am NOT presenting myself here as
"the" expert: I am presenting expert information gathered up in one
place for the public to see that (hopefully) properly summarizes the available
literature. Like I said, email me additions, corrections, etc. The best advice
always is: follow the standard for the breed, in color,
as in all other things. You cannot go far wrong as a breeder if you use the
standard as your guide.
BREEDING
HARLEQUINS: THE BASICS.
First off, regardless
of what combos you try, large numbers of mismarked
puppies are expected in ALL breedings
involving harlequin (& merle) dogs. The best you can ever
hope for is about 75% correct color & pattern;
50% is the average if you count both Harlequin
& Mantle offspring. You can reduce the expected number of correctly marked
pups by at least 1/4 if you want to talk about harlequins specifically. Merles
are routinely born to harls, as are various other
mismarks, including white merles (MM) also known as (deaf) white danes. Therefore the problems of
euthanasia of defective pups and the careful placement of dogs who fail to meet
the standard is a routine part of the responsibility of any ethical harlequin
breeder. You can avoid all of this by breeding Danes of any other family but
Harlequin. Harls have problems & challenges the
other colors of danes
do not face. Mismarks in every litter is just one of them.
HARLEQUIN to HARLEQUIN:
You can expect, in a litter of 7, to see 2 (likely mismarked)
black or Mantle pups, 2 merle pups, 2 harlequin pups & one deaf white pup
(two are statitically conceived, but one of two
whites conceived generally dies prior to birth). Naturally people have 7 males
in some litters, so some people will have 7 harls..or even 7 deaf whites, but on average, about 1/4 of
the four basic colors is what is expected. Of course harls that carry blue or fawn or brindle can produce these
"porcelain" dogs, sometimes called bluekin,
fawnikin & brindlikin
respectively. To read about why fawnikins occur, click
here. Flashy harls (with lots of white)
could also produce piebalds: white dogs with
"mantle heads & harlequin looking bodies" as they have been
described. Harl-, merle- or boston-heads; dogs with white bodies &
"caps" of color (i.e. color-headed
dogs) also can result from the use of piebalds &
flashy harls & mantles. These color-headed
dogs, also called piebalds, are essentially mismarked Mantles. To read more on piebalds,
click
here. Any time two dogs with the merle gene (incl. harls) are bred to each other,
white merle (i.e. defective, dominant white) offspring are to be expected. The
dominant whites that do survive to birth are normally defective & commonly
deaf. Ethical breeders generally euthanize all whites
at birth for these reasons. To read more about white (MM) danes, click here.
HARLEQUIN to MANTLE:
This is the preferred breeding, all things considered, as it does not produce
the Dominant (deaf) White dane.
Expect the litter to be about 1/2 mantle, 1/4 merle & 1/4 harl. So in a
litter of 8, expect 2 harls, 2 merles & 4
mantles. If these black pigmented dogs carry for other pigments, you may get
fawns with blazes, or blue instead of a black basecoat. (If that is confusing,
read about why
fawnikins are here to stay.) Piebald & color-headed dogs can occur, especially when flashy dogs
are used.
MANTE TO MANTLE:
Produces only Mantle. That is, it cannot produce harl, merle or white danes. Now piebald danes that are mistaken for whites
and for harlequins can be born to Mantle parents. This is more likely to
happen when breeding flashy Mantles with big collars & broken blankets than
with dogs who have more pigment. Mismarked blacks can
also be born to this breeding. It is possible (if unlikely!) that very flashy
Mantles bred to each other could produce a puppy so white s/he could be
deaf. Possible--not probable--& AFAIK it's never happened in Danes. BUT it
does happen in Boxers & Dalmatians.
MANTLE TO (harl-bred)BLACK. Would likely produce mismarked blacks. Mantles & (solid) Blacks also
are possible.
BLACK to BLACK: Would
likely produce mismarked blacks when harl-bred blacks
are used. Mantles & Blacks possible.
BLACK TO HARLEQUIN:
Produces as does Mantle to Harlequin, except, since a Black lacks the
white collar of the Mantle, expect more mismarks under the AKC standard to
occur, both in Harlequin & especially in potential Mantle offspring. Blacks
will likely not be solid Black, but mismarked black,
sometimes even called "harlequin black" it is so common to black to
harl breedings. These "harlequin blacks" are
disqualifying under the American standard.
These above breedings are authorized by the Great Dane Club of
BLACK TO WHITE: (or
Mantle to White). This breeding is done by some people because it sometimes
offers the possibility of producing at least 50% harls
or even a whole litter of harls. Of course a whole
litter of merles is just as likely as getting all harls
& there are lots of problems with using whites in a breeding program.
Whites may all look alike, but they don't all breed alike! And of course most
of them are deaf. To read more about whites, click
here. White to black breedings that
produce black, mantle or piebald pups are not true black to white breedings; the "white" used is actually a mismarked harlequin or a misidentified merlikin.
Using deaf dogs in a breeding program is reported to increase the number
of deaf pups thru several generations.
WHITE TO HARL: This
would produce a litter with 50% deaf whites, the rest split between harl &
merle, depending on what kind of white was bred. Again, if this breeding
produces black, mantle or piebald pups the "white" used is actually a
mismarked harlequin or a misidentified merlikin.
HARL TO PIEBALD: This
would increase the number of mismarked pups, as you'd
expect to get harl-heads instead of harlequins & piebalds
in the place of mantles, especially if the harl used is flashy or even just has
that clean white neck. To read more about the piebald, click here. Piebalds are mismarked Mantles, not a kind of Harlequin.
MERLE TO WHITE: 50%
deaf (or dead) white is expected; 50% merle, with reduced litter size due to
merle-related deaths.
MERLE (or merlikin) TO BLACK (or to Mantle): This is a breeding using
TWO mismarked dogs. (Most of the others use at
least one parent with correct markings!) Since some harl-bred blacks &
mantles can carry harl genes (H-factor) unseen & merles obviously carry the
Merle gene, recombining the two can occassionally
produce harls. But mostly, again, this breeding produces mismarks: black
with white markings & merle dogs. And the dogs used in these sort of breedings are commonly
sub-standard in other ways than color.
MERLE TO HARL: This is
like breeding harl to harl, except you reduce your chances of getting harls & increase your chances or getting mismarks and
various defects by all reports.
MERLE TO MERLE: This is
not deliberately done in Danes, although it is occassionally
done in other breeds. It is universally discouraged & is against the law in
some countries. Vague reports of such breedings in
Danes make the rounds from time to time. From what is known, at least 25% or
the litter is expected to be defective & there are anecdotal reports (in
Danes & other breeds) of merle x merle litters ending in
"disaster" (all lethals, all defects,
absorbed litters, etc.) More on breeding merles below:
THE "WHY"
OR RATHER THE "WHY NOT" OF BREEDING MERLES:
1) Merles are a
disqualification under all standards for the Great Dane--and have always been.
That is enough, in many registries, for a dog to be denied "papers,"
so this is obviously always been thought a very poor breeding choice. (That the
AKC will register a dog does not imply approval of it as a breeding choice--the
AKC will register *ANY* dog with two registered parents of the same breed. Any dog.) One must assume, historically, such animals
were used & the results generally not good, hence the fact they have always
been disqualified. There *are* anecdotal reports that using merles in a harl
breeding program not only increases the number of mismarks in a litter, but
also results in a much higher number of defective puppies than in a harl to
harl breeding. In other breeds which allow the merle (very few BTW), merles are
not supposed to be bred to each other, to avoid the production of white merles:
those defective, predominately white pups. Merles LACK the necessary genetics
on their own to produce harls: noone
has ever documented a merle to merle breeding that produced harls.
So by all reliable reports, merles as a group do not productively contribute to
the harlequin-mantle gene pool.
2) It is certainly and
always the case that anyone who has not established an *sterling* reputation
& can explain to the general dane fancy's
satisfaction the reason to break such a general rule of breeding better be
prepared to be considered unethical by most if not all others concerned about
ethical breeding. This is a case where making an exception to the rule is
better NOT done but for the rarest of cases where the person in question has a
long track record of good practices, the production of Champions under ethical
constraints, AND who has an exceptional & rare enough situation on their
hands to warrant a probably once in a lifetime event. People who sell &
breed merles (including so-called merlikins) as
breeding stock on a regular basis can simply be generally assumed to be
commercial (i.e. for-profit) breeders whose goal is cash cropping harl pups,
not breed protection. These dogs are also bred in ignorance by people only
casually involved with the breed. Needless to say, however well meaning, these breedings do not contribute to breed betterment either.
3) A
4) "Merlikins," a white base-coated dog with black and
grey markings, have been bred on occassion to Mantles
to produce harls. But this is a risky breeding for
several reasons. Merlikins may be deaf and have eye
defects (and without a CERF no one can say a dog's eyes "are fine"!),
most (Mm) merlikins will NOT produce properly marked harls under any circumstances, & the harls they DO produce are likely the result of their Mantle
(boston) mate carrying unseen the factors needed to produce harls.
There is significant evidence that some (many?) merlikins
are actually (MM) double merles, i.e. genetic whites. There is also a
well-established theory that merlikins are simply
merles which carry the
5) The long and the
short of breeding merles (and other mismarks, for that matter) is, if you have
to ask about the whys and wherefores, you probably "can't afford it;"
can't afford the disaster and dishonor likely
awaiting you. Unless you are dealing with a publicly esteemed breed expert
really caught in a corner, you can pretty much assume someone using mismarks
(e.g. merles, piebalds, and other mismarks) routinely
in their breeding program is less than knowledgeable and less than ethical.
This *is* a case of guilty until proven innocent.
WHAT ABOUT THOSE
MANTLES--WHAT ARE THEY AND HOW TO BREED THEM?
I published an article
in the Great Dane Reporter in 1997 on the action of the S Locus itself (when
alone) as it applies to the Mantle (Manteltiger)
entitled: "Mantle Dane Genetics: How to Get & Keep Boston
Patterned Dogs". There are also
somewhat harder to find, but very useful, articles published over the past two
decades by such as Paul Hardiman and Laura Kialenaus on the subject of the Mantledane.
I tried to summarize their message in the article I wrote in 1997. This article
discussed some of the implication of attempting to stabilize a
"tux-n-tails" bicolour Great Dane as a breeding partner to the
Harlequin. This also is a complex issue, but the basic take home message is:
1) Breed only properly
marked Harlequins & Mantles to avoid not only mismarks but an increase
(thru loss of pigment) of pups with sensory defects. The breeding of piebald or
flashy boston-type dogs (those with extensive white, i.e., more than 1/3 white)
will result in a loss of harl offspring (to such as "harl-heads"), and
could cause an increase in defective pups due to loss of pigment from these
recessive white genes combining with the dominant white gene(s) that make up
the merle/harl complex. Therefore, avoid the breeding of mismarks, especially
predominantly white mismarks, such as harl/merle and
2) Attempting to
stabilize a full and complete collar and the approximately 1/3 white called for
in the ideal of the Mantledane requires one to
'straddle' a gap between two alleles (si=irish and sp=piebald)--SO--many dogs with this same
phenotype are going to have VERY different genotypes & most of those
genotypes are NOT going to be homozygous (e.g., Ssp/se
= pseudo irish occurs). The long and the short of
that is, that many Mantledanes who look just alike
are going to produce very differently, & the more mismarks used in
the breeding program (especially predominately (>50%) white dogs), the
more mismarks that can be expected, especially "skip
generation" recessives. Consider the problem with whites and checks in
Boxers, as this is the exact same phenomena-less our problems with the merle
gene. What is called "white factoring" occurs in these breeds--i.e.
the presence of a piebald recessive white allele--which results in
predominately white dogs from predominantly pigmented parent. This phenomenon
is present in a variety of breeds from Collies to the
Checks
& whites? If
not familiar with this phenomenon, see how "Plain,"
"Flashy," & "White" phenotypes in the Boxer (roughly)
corresponds to Solid Black, Mantle & the Piebald in Danes. Click here for an illustrated tour of this
two gene, three phenotype phenomenon typical of incomplete dominants.
See also "Spots Before Your Eyes" for an
illustrated guide to the complete & complex phenomenon of the recessive
spotting (S) locus with its four alleles, incomplete dominance, 10 genotypes,
modifiers, & multiple, overlapping phenotypes, which is likely a much
closer analogy to the situation in Danes.
3) It would seem
inescapable that some & not all Mantledanes carry
some sort of allleles, be they modifiers or a more
"direct" & seperate H-factor (the
"harl" locus), that contribute to the production of harls (over merles) in harlequin litters. This is implicit
in much of what has been written, but is rarely explicitly stated. It certainly
should be addressed at part of the family inheritance, as should the
implication that follows directly from this observation; namely that Mantledanes, as individuals, contribute
"unevenly" to the production of harls, with
some unable to offer any "help" to increase in the percentage of harls in a litter, while others might, at least under
certain theories, carry strongly enough for whatever constitutes
"harlequin genes" to not only increase the percentage of harls in a litter (over merles) from a harl x mantle
breeding, but actually produce harlequins from a merle x mantle breeding.
THE TECHNICAL STORY: MERLES TO HARLS--AN INTRODUCTION & MORE
There are a variety of
theories publically offered to account for the
variation of harl to merle phenotype. These I have summerized
and discussed in detail in the 1996 publication entitled: "A
Summary of Theories concerning the Harlequin Variant in the Great Dane." (published in the GDR (Great Dane Reporter) May/June 1996
issue). Generally all these theories fall into the following categories:
1) Harl is a variation
on merle, with the M allele of merle being somehow modified to produce this
different phenotype. Various ad hoc caveats are added in to explain observed
phenomena that do not fit the specific theory. None of them (e.g. Burns &
Fraser) are at all satisfactory & most cannot account for the (regularly
observed) production of merles from harldane breedings. If you read in such as Willis, you can see some
reports on such theories. As they don't match with observation & data, they
have generally been discarded & are included here simply for thoroughness.
2) Harl is a variation on merle, with a seperate
Locus being necessarily present to produce the harl variant (the W/H theories
of harl). This is the Bagalla (W) or Sponnenberg (H) theory of Harlequins, that Neil O'Sullivan
published on (with comprehensive statistical data) & Jane Chopson so thoroughly diagrammed.(To read this explanation,
click
here.) The basic notion here is merles lack a gene that harls have. This "H gene" makes harlequins by
"clearing" the grey background that the merle gene leaves behind. So
merles are grey dogs with black torn patches, whereas harlequins are white
dogs with black torn patches. Harls are HhMm; Merles are hhMm. Harls are therefore "H-factored" merles if you
will. Merles, therefore, cannot produce harls as they
lack this H-factor. There are no living homozygous (HH) harls,
as homozygosity is uniformly lethal. There are homozygous
or "white" merles (MM) however, although about 50% of these dogs are
also lost prior to birth. (To read more on the white or white merle dog, click
here.) So, the merle allele is sub-lethal as is the harl allele, but
both seem to be generally deleterious only to the homozygote, and the link for
both deaf & defect is not direct, but rather thru the loss of pigment &
pigment cells. (See below for more information on Dominant White Lethals.) MM loss produces a 12.5% (1/2 of 4/16)
reduction in expected litter size. HH loss produces an additional 18.75% (3/16)
loss in litter size. Together under this theory a 31.25% loss is expected.
Merle x merle (hhMm dogs) cannot produce the
Harlequin variant (a HhMm
dog). Merlikins under this theory are simply
heterozygous (Mm) merles who are homozygotic for the
recessive
3) Little's original (1955) theory is that harl is
simply a phenotype variant of merle, with the action of alleles at the S locus
(in combination with the M allele) producing the variation from merle to harl.
This has been thought to be an incomplete, if not wholly inadequate theory for
a variety of reasons which revolve around explaining all the multitudinous
variations of harl to merle & the observation that MmSs
or even Mmss does not seem to produce harl in any
other breed but the Great Dane. If expanded, this could be called the Modifier
Theory of the harlequin variant. A suggestion I made in Yousha, 1996
was that M modifiers (functioning quite like the recognised modifiers at the S
Locus) might account for the declaration made that merle to merle breedings can produce harls (which not all other theories cannot account for). And a
"Modifier Theory" of the Harlequin variant does not require the
31.25% expected reduction in litter size that the H-factor Theory would need to
function, so might better account for the large litter size not uncommonly
reported in harl-family dogs. It also fully accounts for black to white breedings which do not produce harls,
as well as those "in-between" "harlie-merle"
animals; the wide & seeminly continuous
variation in phenotype seen in both harls &
merle, and the commonly reported claims of merle to black dane breedings producing harls. In short the idea of such a Modifier Theory is that
merle is a phenotypic continuum with two axes: S for pattern distinct from M
for coloration(hue). Modifiers genes at the M Locus
"add" & "subtract" pigment, particularly from (merle)
areas of reduced ("dilute") pigment that appear grey-brown. Many
positive modifiers allow for a merle phenotype and as these modifiers
"move" to be predominately negative, harlequin phenotype begins to
appear. Modifier genes from the S locus account for the incremental variations
from solid (mouse) merle through boston & piebald merle, merlikin, color-headed dogs, as
well as "clean white necks" & other overall pattern phenomena
seen in harls. It is a complex & somewhat
unwieldy idea; and without clear categories (since it constructs a continuum).
We know recesive white (S Locus) spotting genes interact with
Dominant White (M/H Loci) genes when it comes to the percentage of white
overall (with more defects resulting in dogs who carry
recessives at the S Locus). This is something observed in all
breeds that carry the merle gene, not something particular to danes. Little (1955) postulated a
synergism occurs via positive & negative modifiers of the S Locus acting on
the M allele, which act to increase or decrease the amount of pigment the main
S gene. The S locus is documented as a late acting pattern locus involved in a
very specific action at a late (embrionic) stage
& acts naturally on the extremities inward, (in a well documented and
somewhat predicable pattern), and is affected by modifiers which allow for a
variation in range around the axis allowed by the main gene (e.g.
S=<10%white, si=<30%, sp=10-90% white &
se=>90% white). The more recessive the allele & the more negative the
modifier series, the early the action of the gene begins to interfer
with A/E Loci (which direct for a fully pigmented body). The M Locus begins to
act very early in fetal development (i.e. neural
crest stage), with full expression occuring later in
development & independently in (molecular leve)
action from the S allele(s). The dominant (M) mutation affects the melanocytes prior to/during pigment migration, disrupting
the resulting banks of cells' ability to produce pigment, thus causing the
mottled coloration. The dominant (H) mutation (or such modifiers that otherwise
exist) is not expresssed except in the presence of
the Merle allele: when H & M alleles are combined, a
Harlequin results.
The HH homozygote is 100% lethal in embryo. The MM homozygote is ~50% lethal in
embryo. The MM (the double merle, white merle, or defective white) danes that survive to birth
generally suffer from sensory defects (e.g. deaf &/or blind) as this gene's
effect on melanocytes affects much more than simply
external coloration (i.e it is pleiotrophic),
although these effects are neither uniform or universal. Their combined (M/H
& S Loci, plus modifiers) effect is to visually increase the amount of
white on the dog. But these genes disrupt the proper formation of pigment. The
S (spotting) Locus, however, simply "clears" areas where no pigment
will normally be found, leaving smooth "edges," white skin and a
distinct bicolour dog. S=spotting alleles are inherited recessively & the S
Locus demonstrates incomplete dominance. (To read more on the S Locus as a
distinct phenomenon, click here.) The M (merle) Locus apparently
affects (fetal) pigment cells individually,
completely disabling some cells (white areas), partially allowing for pigment
expression (merle areas) & having no affect on some cells at all (black
areas). Mottling or merling, with
distinct "ragged" edges & a random blotching pattern of varying
hues results. The M allele can only act, however, in the areas
unaffected by the restriction of pigment due to carrying recessives at the S
Locus. The H allele (or modifiers) cannot act except in the presence of the
Merle allele, as detailed above. So merles are without the H-factor (if they
had it they would be harls). But blacks (including
Mantles) with the H-factor are simply black in appearance.
For more info on neural
crest development see: http://www.teaching-biomed.man.ac.uk/student_projects/1999/moran/
or http://www.google.com/search?q=neural+crest+development&btnG=Google+Search).
Their respective biochemical action of these recessive &
dominant white (spotting) genes seem distinct & discrete, but the
combined result is a dramatic loss of pigment. This fact is worth taking
account of as lack of pigment is not simply an aesthetic factor. Loss of
pigment & pigment cells affects the structure and functions of many organs,
particularly eyes, ears & skin. So "pretty" predominately white
dogs are distinctly at a functional (and reproductive?) disadvantage &
(even inadvertently) breeding to increase recessive white in merle/harl dogs is
a practice that can be predicted to increase the number of defective
heterozygous (Mm) (lightly marked harl, white bodied & merlikin)
dogs.
***SUMMARY***
Naturally the same
data are all explained by all these theories outlined above. There is no basic dissagreement about that. There is no dissagreement
about what is expected or seen in harlequin litters. Also there is no
disagreement about the data produced or the information given above the
"Technical Section" above. It's simply a question of more than one
theory that fits the data at hand, which is not uncommon in science, &
really has little practical significance to breeders anyway. The details of
harlequin genetics that these theories differ over are fairly insignificant
& mostly are just an intellectual puzzle. It cannot be said that there is
any real mystery or controversy about harlequins & the merles they produce
( at least for educated breeders), and quibbles over theory details should not
be used to exploit the breed by mating all sorts of dogs, or claiming breeding harls is uncontrollable or wildy
unpredictable. This is simply not so. Color genetics
is the "crayola crayon" level of genetics:
easy to manage and easy to comprehend compared with more complex (& more
important) genetic issues that affect dogs & breeding decisions. And it
cannot be said too often that the general rule of breeding harlequin family
dogs is to use show-marked & breed-quality animals only.
In summary, the
Merle mutation is a documented incomplete dominant with 3 distinct phenotypes (e.g MM Mm & mm) possible. The
phenotype harlequin, as a distinct "fourth" type, is somewhat
controversial, but is obviously present at least as a phenotype, even if it is
only (apparently) found in the Great Dane. Since Little's original notion of modifiers was not
developed enough to satisfy Harlequin breeders & his data were apparently
limited, other theories have been postulated to better agree with current data
& observations. The most widely accepted theory for the Harlequin variant
was postulated by Sponnenberg & by Bagalla, is supported by the work of O'Sullivan, &
explained in precise detail for laymen by Jane Chopson.
If it were ever to be documented that a true merle to merle breeding produced a
true harlequin, however, this theory would be discredited, as it does not cover
than contingency. This theory also requires fairly large (~1/3) litter losses
due to lethal gene combinations. The notion I suggested of M as well as S
modifiers allows for harl offspring (if rarely) from merle dogs, and does not
require such massive litter losses. It offers more "moving parts" to
explain the wide variation in pattern & pigment seen in both merles &
harlequins. (It also makes the whole process of figuring out "who has
what" rather unwieldy!) But of course it does not offer a molecular
or actual physical explanantion; it is just a
theoretical explanation that remains "undefeated" in the face of the
recurring (but never documented!) reports of merles producing harls, and does not require such a large reduction in
litter size from fetal death. But whatever the
"physical truth," the easiest way to practically predict offspring is
to use the H-factor theory, even if it is used only as a sort of shorthand for
details still not in evidence. I suspect we will all have to wait for the
molecular data for a detailed answer as tothe
question of what exactly makes harlequins genetically different from merles.
Please note that, regardless of the theory to which you subscribe, it is
inescapable that the current trend in American harldanes
to produce ever "whiter" harldanes has
negative implications for the overall health of the resulting puppies as well
as producing a whole series of recessive mismarks uncommon (in not unknown) in
the parent stock. The original selection was for a strongly
pigmented dogs & ONLY the AKC standard calls for a "white neck
preferred." FCI and all other Great Dane standards (including the parent
country) simply ask for a black and white dog with "torn patches."
They generally allow solid blacks & even our "mismarked"
blacks to be used as part of the harlequin breeding program, but frown upon
black dogs with extensive white markings; presumably to avoid the production of
recessive white dogs in a color which already carries
for dominant white. So even when breeding for this "preferred" (AKC)
white neck in harl & mantle danes,
one should not lose sight of the following facts:
1) It is never possible to control for a predicably
fully white neck, even when two such animals are bred consistently together;
the genes (as described above) do not admit of such control. So it is not a
trait worth giving an enormous amount of attention to, and the standard for the
Mantle doesn't require a fully white neck anyway.
2) Even the AKC
standards say NOTHING about white "fronts" & chests and forelegs
being even desirable, let alone preferred on harls or
mantles. Note also the illustrated standard says markings on the neck &
legs, etc. of a harldane are NOT to be faulted. So
faulting those equally correct dogs is short sighted, even if certain patterns
within the accepted range are fashionable or even more aesthetically pleasing.
3) Since harl &
mantle dogs of less than ideal pattern are inevitably necessary to a breeding
program, it is best to stay within the acceptable range of pattern as
documented by the illustrated standard. All sorts of romantic legends about the
value of mismarks in breeding programs abound, but it's a simple fact that no
truly dedicated breeder would ever prefer a mismark
to an animal correct to the standard. Apart from there being absolutely no
documentation that mismarks "help" produce harls
(in fact the evidence is quite the contrary), it is also obvious far too many
mismarks are included in breeding programs simply as a cheap way to make harls.
4) Mismarks make
more mismarks. Even if harls cannot breed
"true," they & their mantle mates produce more correctly marked
animals than mismarks do. And the problem with breeding & getting harls is not liscence to sell and
breed every imaginable mismark that comes out of a
harl litter. Many of these myths about the value of breeding mismarks are so
obviously self-serving. Many who breed them are simply uneducated about
harlequin genetics it would seem. The mismark who is of actual breed value is a rare creature from an
unusual breeding. Predominately white dogs from harl breedings,
if kept, should be BAER & CERF tested, according to DDC (German parent
club) recommendations. Deaf/defective dogs used in breeding programs appear to
have an increased incidence of deaf/defective offspring, even several
generations later. Something to think about, as losses of normal & useable
animals are to be expected when deaf dogs are used.
5) When using dogs
either under or over marked, it is better judgment (if less the fashion or the
common taste) to use dogs with more, rather than less pigment.
This was the original intent of the standard of the country of origin & is
still so designated in most standards worldwide. The AKC standard for the Great
Dane has altered its color description during various
revisions for a dog with more white than called for or originally prefered. It is obvious for better health that more white
is less prefered.
For us to have the
CORRECT harl & mantle range of color put up in
the ring, we have to show the judges the correct range of acceptable markings;
not some individual (or group's) aesthetic choice, or a fashion of the
times--but TO THE STANDARD for the purpose of breed preservation. For us to
safely breed dogs carry "lethal" & "semi-lethal" genes
we need to consider the implications of simultaneously carrying 2-3 white genes
well documented to cause serious health defects when "used to excess"
to produce predominately white dogs. We should not encourage an increase in
defects purely for the sake of a (currently) prefered
aesthetic, sale of breeding stock, or ease of breeding choices.
And as not to forget
the art in the science (of breeding), I offer this short poem by Gerald Manley
Hopkins, who surely would have included in his beloved "dappled
things" the glory that is the Harlequin Great Dane.
Glory be to God for
dappled things--For skies of couple-colour as a brindle cow; For
rose-moles all in stipple upon trout that swim; Fresh-firecoal
chestnut-falls; finches' wings; Landscapes plotted and pieced--fold, fallow,
and plough; And all trades, their gear and tackle and trim.
All things counter,
original, spare, strange; Whatever is fickle, flecked
(who knows how?): With swift, slow; sweet, sour; adazzle,
dim; He fathers-forth whose beauty is past change; Praise him.
(Gerald Manley
Hopkins)
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1998 (revised 2001) J P Yousha, CHROMADANE. All rights reserved. Our thanks to the willingness
to share this article for educational purposes.