OF PEAS AND PUPS
PART VII
DR. BUSTEED, GENETICIST
AT WEST
RELATIONSHIP:
In considering the
relationship between two dogs, we usually turn to the pedigree. Without
knowledge of the diverse actions of the genes, of their sample having process, we might well
imagine that pedigree relationship and genetic relationship were one and the
same. Of course they need not be at all. The probability is that considerable
correlation between the two does exist. The consistency of this correlation
drops off rapidly as we climb the family tree. The dam to daughter relationship
is 50% and can be no other way, although the rearrangement may hid the fact. The grand-dam to grand-daughter relationship
can also be 50%....or it can be zero. The probability is that it will be about
25%. So from a standpoint of the genes, a dam and daughter must be related but a
grand-daughter need not actually be related to her
grandmother....if she gets none of her grandmother genes, she simply is not
related to her from a genetic standpoint.
A strain is a family within a breed. It
properly indicates relationship. There are few true Shorthair strains in the
Bloodlines connote a similar relationship
but since blood actually has nothing to do with it, the term should be dropped.
The only way one dog can get blood from another is by transfusion...or
fighting. It is a hold-over from the old "blending days" and enjoys
such common usage that it will probably remain. If we
realize its limitations, it may have some value....The resemblance of
individual dogs in various strains or bloodlines is a result of their
relationship...common genes. This is due to the similarity of genes they
receive from common ancestors. It is probable
that the closer the pedigrees agree, the more genes two dogs will share in
common and therefore the closer related they are. It is a certainty that the more genes
two dogs share in common the more closely related they are...whether they share
any close, common ancestors or not....The important point in relationship, for
the breeder, is
genetic similarity...not pedigree similarity.....Although this thinking may be
contrary to our usual thoughts about relationship...it is the genes that are important,
not the paper! The possibility,
not the probability, that the two may be poles apart...that things are not
always as they seem...forms the crux of the problem of defining specific
breeding plans. It cannot be done with certainty.
All living matter is
probably related...share some genes in common, and its position on the
evolutionary ladder determines, to a extent, that
relationship. All dogs are related to the wolf in that they have some of the
same genes which once occupied the nucleus of some ancient wolf. We ourselves, have some genes which once lived in the Garden of
Eden, and so far, only the Lord knows how they got there. And so we are
related, in some small degree to our dogs, genetically as well as spiritually.
Every Shorthair is
related to Hector I, whose parents were unregistered. The degree of
relationship is small, none the less, it is there. It is difficult to see that
relationship in a picture. Hector was a large, liver and white dog...solid
liver head an a long tail. He had no ticking and his
large liver spots covered much of his back and rump. He was a nice looking dog, yet, we are forced to admire the Art of the German
breeders for the great improvement witnessed in less than a century. Hector I
was whelped in 1872. Generally, any relationship beyond the fifth generation is
an unimportant consideration since it contributes less than 2% of the blood of
a litter. No matter how famous that fifth or sixth generation ancestor is, he
has probably contributed little to the pups. The nearer (in pedigree) any
individual is, and/or the more times his name appears, the more important his
contribution (for better or worse) is PROBABLY going to be. It is the "ART" of breeding
which can tell us if pedigree relationship and genetic relationship are one and
the same in any given dog and "papers" are no substitute for art.
Below is diag rammed the probable percentage of genes
contributed to a litter of pups by various ancestors.......
There are two kinds of
relationship. Direct
and collateral. The mechanism is much like our own blood
supply. Large arteries go directly
from the heart to the important organs. Should any of these arteries become
blocked by injury or clogging the blood continues to flow by a detour route to
that organ. The blood gets there, usually in less than ideal amounts, by a
round about path and the organ is served by this collateral blood supply. The relationship is
direct from parent to offspring. It is collateral when both animals descend
from common ancestors, as brothers, cousins, etc.
Father and son are
directly related as A to B and H to I. A
& H are collaterally
related. They are cousins and have probably received some similar
genes from their common grandparents. They could have received 25% from each
grandparent, D & E, and they probably did; but this is not a certainty,
they may have received no "blood"
from D or E. The degree of "blood"
relationship and direct relationship are the same, however, due to the sample
halving nature of inheritance, this is not also true of collateral
relationship........The Champion Bob
Koege, may not be a familiar name to many,
yet it is a fine example of thoughtful breeding and a worthwhile demonstration
of percentage of blood.
It is my thought that it is the planned inbreeding of Bob Koege
in his native land (Denmark) coupled with the wise and artful inbreeding in the
U.S., which accounted for four of the five Shorthairs which made the GSP
All-American Sporting Dog Team (Sports Afield 1963 -
reported February '64), as well as 3 of the 4 top places in the 1963 AKC Nat'l.
This is inbreeding that you can even read in a pedigree. But back, now, to Bob Koege.
Do you think this pedigree just happened???
There is a relationship
between all animals which have a pair of genes in common, as AA, Aa & aa.
And it may seem ridiculous to reduce relationship to a single pair of genes out
of thousands, yet, it may serve to crystalize
the idea of genetic relationship, which after all, is the important thing. If
all GSP'S had but one gene pair, all AA's would be so closely related that the
mating of two such would be the equivalent of self-fertilization. The
relationship of AA animals to aa's would be as
distant as possible in the same breed, whereas, Aa
and Aa Shorthairs would be closely related to each
other but only 50% related to either AA or aa
dogs.....In a litter of four pups from Aa - Aa
parents, AA, Aa,
Aa, aa, would
find two pups as unrelated as possible for the breed, AA and aa;
two pups as closely related as possible for the breed, Aa and Aa...These
Aa
pups would be 50% related to the AA
pups and the aa pups, which is the
average relationship for pups of a litter....
Let us explore genetic
relationship...the relationship which becomes closer as the number of genes in
common becomes greater. Arko and Annya
are litter-mates, full sibs. Their sire, Birko and
dam, Coko, are not closely related, they share in
common about as many genes as is average for the breed; they are heterozygous
for the "A"
gene, "Aa".
Arko might get "A"
gene or "a"
gene and Annya might get "A" gene or a "a" gene from the
sire, Birko. The chances are ½ that one pup will get "A", too. thus the chances that each will get "A" or that each will
get an "a"
is 1/4 (½ x ½ = 1/4). Since the odds are the same (1/4) for these genes from
the dam, Coko, the relationship of the pups through
both parents is ½ (1/4 plus 1/4 = ½). They are 100% related by
"blood" but probably genetically related by 50%. Half sibs, since
they are related through only one parent, sire or dam, are related by
25%....Another way we might look at it that Birko
gave ½ the genes to each pup but it could have been either of two halves and it
is ½ chance that he would give the same half to both Arko and to Annya. Thus, Arko and Annya are each related
to their sire by ½ but are related to each other through their sire by 1/4. Since they are both
related to their dam by the same odds, they are probably related to each other
by ½, 1/4 coming from sire and 1/4 coming from their dam. All this may seem
interesting but impractical, yet since wise breeding plans depend upon the
relationship of the partners this knowledge is fundamental to an understanding
of breeding methods.
The coefficient of
relationship, (Rx), will provide for us the probable percentage of like genes each
animal possesses, above the average for the breed...it
will give the relative genetic relationship of two animals. Although, at first
glance, it may look like hieroglyphics or something concerned with nuclear
physics, it is based upon the sample halving nature of inheritance and is not
too complicated for simple relationships. This formula does not take into
account the added homozygosis due to inbreeding of common ancestors. It can be
adjusted to account for this, but it gets pretty complicated where much
inbreeding has taken place and in its present form will accommodate 85-90% of
all Shorthair pedigrees with reliability.
"R" IS THE
COEFFICIENT OF RELATIONSHIP. (Rx)
THE GREEK
"SIGMA" IS THE SUMMATION.
"N" IS THE
NUMBER OF SAMPLE HALVINGS BETWEEN ONE COMMON ANCESTOR AND THE FIRST DOG WHOSE
RELATIONSHIP WE ARE FIGURING. (ARKO).
"N1" IS THE
NUMBER OF SAMPLE HALVINGS BETWEEN THE SAME COMMON ANCESTOR AND THE OTHER DOG WHOSE RELATIONSHIP WE ARE TRYING TO ESTIMATE. (ANNYA).
"R" IS THE
TOTAL OF THE RELATIONSHIPS WITH ALL ANCESTORS BOTH DOGS HAVE IN COMMON WITH
EACH OTHER.
Arko and Annya
are full sibs...if they were half-sibs, had only the same sire, for example,
they would be related by but 25%. Their Ra-a would be
.25. Let's see how closely full cousins are related and then call it
quits.....A and Z are cousins and share one pair of grandparents in common.
Their Ra-z is .125 or 12½%. They probably share 12½% more genes in common...in
the homozygous genes in the breed as a whole is 10,000 out of 20,000, first
cousins would share 11,250 genes in common.....Double first cousins, dogs which
shared two grandsires and two grand-dams in common, would have an Rx just twice
as great as simple first cousins, .25 or 25%. They would likely share 12,5000 genes in common out of 20,000.
INHERITANCE
INFLUENCING INSTRUMENTS:
One heat per year, as
in the wolf, is dominant to two heats per year, as in the dog. The pointing instinct is incompletely
dominant to its lack...Hunting with high head is dominant to hunting with low
head. Love of water
is dominant to the preference to remain dry. These facts, gained from species
crosses (cross breeding) are interesting and they demonstrate that even
multiple gene groups follow the same hereditary patterns which control single
genes....In some instances, they may be a practical application, but generally
they are about as utilitarian as two tails.
The great good of Mendelism, stems from broad general implications rather
than the action of single genes. We are mating thousands of genes sealed in
animated liver and white envelopes. In spite of all this talk about the genes,
the dog itself is the smallest unit of selection. Fortunately...for it is impossible...we
need not isolate the gene pattern of our dogs before taking advantage of Mendelism.
Wise breeding is the
practical application of genetic theory (guided by an artistic hand). Actually
our knowledge of the operation of the genetic system is reasonably complete. We
know many of the why's and wherefores' which the
pioneer breeders did not. The breeding tools they used to fashion our versatile
"barkensniffers"
are the same ones we must use to improve them. These tools were made of good
steel. They were primitive only in that their action was not understood. We are
indebted to science for having honed much of the roughness from these crude
edges and having made available sharper and more effective instruments. The use
of these improved inheritance influencing
instruments can speed our progress and reduce our errors.
Breeding takes some knowledge, some art, some planning and some luck...not necessarily in that
order. Our efforts here are to supply "some
knowledge". Breeding is a game. It has strict rules. We can
use only the genes in the breed itself. We are unable to break Mendels laws even if we try. We
cannot change the number or the linkage; we cannot control the segregation. We
cannot take the nose genes from one dog and combine them with the run genes of
another and the conformation of a third in a single mating. Our selected sire
will produce a great array of genetic sperms and they will unite at random with
whatever eggs the dam produces. We must accept the results. We have our work
cut out for us! Bound by these restrictive odds, if we are to have a fighting
chance, we must use every tool in the book. Even using every tool, in what
appears to be its proper place, will not assure a winner.....Picture Mickey
Mantle standing at home plate with a ping-pong-paddle in his hands - we could
hardly expect a home run...Put a 36" Louisville Slugger in those same
hands and the odds are considerably changed. Of course, he could strike out,
but with the right tool, the possibility,
at least, is there. The analogy can be carried a step farther...Mantle is a
true artist, in his own field.....The breeder has but
few tools with which to manipulate the genes in his animals. Not one of them
used alone, will prove effective over the long haul...we must use all of them.
The tools are these...there are not others.
1. SELECTION,
which is not only a tool itself but is also the "handle" for each of
the other tools.
2. MATING LIKES
TO LIKES based on appearance and/or performance.
3. MATING
UNLIKES based on appearance and/or performance.
4. INBREEDING
mating of likes with regard to ancestry. (genes)
5. OUTBREEDING
mating unlikes with regard to ancestry. (genes)
Since there are varying
degrees of each tool and since all are used either in combination or
alternation with each other, there are innumerable breeding plans based on
these few tools. Before discussing each tool, so that we will then be able to
formulate a breeding plan of our own, it seems advisable to face some of the genetic
problems encountered
by an average Shorthair owner in a typical mating. By this plan, we can
demonstrate the steps, the tools, their use and abuse, the probable results,
and best of all, we can produce a "paper dual" on our
first try. This will provide a brief overall picture of the practical side of
genetics and will show how the parts fit together to form the whole. The parts
will then be covered separately and in detail when their practicability and
necessity have been demonstrated.
In this hypothetical
instance, since our prime topic is genetic, we must assume that our artistic
judgement is correct. "My name is Bill Sneider, I have a sweet
little Shorthair bitch, Annya.
She's sharp as a tack in the field...made her championship by 3. She's a great
little duck-dog and hits the water like a ton of bricks. She's a doll around
the house and a real member of the family. We think she's perfect but some of
the show fans down at the club say she's got a weak rear end, whatever that is.
We want to breed her right. How do we go about it?" This problem, or one
like it, faces the average Shorthair owner several times during a lifetime. How well the problem is met, will do much to determine breed
improvement in the years ahead. Genetics itself and alone, as we have
said, will not assure success but it can definitely tip the scales of
probability in our favor.
Selection is the first
step. Annya
has been selected. Now we must select her mate. This is more often the problem
and it is a bit more difficult than selecting a pair to be mated. We will say
that Annya is mildly line bred (line breeding is the respected form of inbreeding)
for if she is the result of a chance or random mating, our problems are
compounded and success, should it ever come, will be delayed several
generations. So she was selected....not really, because she was just
there...she was loved...she was the only dog-member of the family....her field
and water work were good...her field and water work were good...her
conformation was weak. In selecting her mate, we will measure his value by the
yardstick of our first two "selection
handled" tools. We will base it on his performance and appearance. We will seek a
sire which is like
her in his performance but unlike
her in rear end assembly. We will use both these tools in this instance. We are
aware that phenotype and genotype may not be equal however,
the chances are that the more favorable Phenotype
also presents the more favorable Genotype...and we
are after the best odds we can get.
At the next club fun
trial, Bosco
shows up and takes the derby. He has a strong rear...good angulation...nice
tail-set and carriage. A perfect match for Annya...based
on these two guide lines. (How easy things work out on paper). Not a few
would end their search here and mate the two, and they could do worse. But why
handicap Annya
and her litter? Are there no other genetic tools which might further enhance
our chances for success? Of course there are...inbreeding and out-breeding.
Which shall we use and why?
Again, we cannot read
the genes, so we must take that which offers the greater possibility of
success. Bosco,
from his pedigree, appears to be mildly inbred and although he has sired but
two litters, the pups looked promising. He and Annya are not closely
related, they share a common ancestor or two in the fifth generation. Their
mating would be a theoretical outbreeding. As we
said, Annya
is line bred. Is this weakness a characteristic of her strain? It doesn't seem
to be, although her grandmother showed some weakness there. Let's see what we
can find in her strain. Beiber is of the same strain
and has a nice rear too, but a check of the pedigree indicates that they share
the "weak-reared"
granddam. Maybe it didn't come from her but why take
the chance if it can be avoided? Cid
placed third in the
Now we shall use our
next tools and see how each measures up. Bosco is
inbred but not clearly related to Annya. Cid is a bit less inbred than Bosco but he is more closely related to Annya who is line bred. Which breeding tool...inbreeding
or outbreeding...would be most effective in this
instance? The best characteristics, if they do not show up in the pups and the grandpups are
not bringing breed improvement. Our decision was to mate (lightly
inbreed) cid and Annya. This, we thought, should produce five favorable genetic results, all of which would be less
likely with Bosco
as the sire.....1. Maintain strain type. 2. Strengthen the rear end assembly of
the pups. 3. Reuse heterozygosity (different). 4.
Provide a place for the pups to go when they reached breeding age. 5. Increase prepotency. The results justified our decision when the
only three of the pups to be fully campaigned made dual. See how easy it is on
paper!
"Now, if Annya were the result of a chance mating, how would this
affect the use of these breeding tools in the overall plan?" That's a good
question. I'm glad you asked. It would make no change up to the point that we
had selected Bosco and Cid as possible sires for Annya. Breeding either dog to her would be an outbreeding, so it would be impossible to inbreed without
finding another sire. In this case, we would use Bosco as the sire
because he was a bit better dog than
Cid but more especially because he was more inbred than Cid and therefore more likely
to be prepotent to Annya. This mating could
not expect to produce the results that the Cid-Annya
mating did, when she was considered line bred, although we know that it might.
For the Bosco "chance-mated" Annya litter to reach the same degree of homozygosity as the Cid "line-bred" Annya pups, would require several
generations of thoughtful planning. We might take best-bitch-pup of the Bosco-sired litter and breed her to a good Bosco-cousin....we do not want to get too close because we
still have some mixed-up genes floating around. We must feel our way slowly but
stay in Bosco's line. If the F2's turned out OK, we
might get closer to Bosco in the next litter...we
would know more about him by then. By F4 we might try the old adage which has
proved successful on occasions in the past...all other genetic factors being in
agreeance...*"let the sire of the sire be the
grandsire of the dam." Maybe by F4 or 5, we might have approached the
quality, the homozygosity, the prepotency
of the Cid-Annya litter. This we could discuss for
hours but will not.
In brief, that's the
overall picture. It is the surprising results which sometimes pop up in
individual litters which add zest and uncertainty to this intensely interesting
game. Without this sporting element, breeding dogs would be just another hobby.
If we play the game by the rules and take advantage of everybreak
that fate gives us, the law of averages will be working for us and we cannot
fail. The greatest stimulus to breed betterment over the long haul is prepontency...homozygous dominance. We can build it...we
must build it. If, when faced with a breeding problem, we ask which tool will
tend the most toward homozygous dominance, the anser
to that will probably solve both problems.
**"Some of the
great prepotent dogs have derived from pedigrees which
seem to show no close inbreeding; but the inbreeding is there...like genes have
met. And when like genes have met in the zygote, inbreeding results."**
* See Part VIII. Fig. 37. Pedigree of K.S. QUITT SUBWEST.
** The New Art of
Breeding Better Dogs.
Part 1 | Part 2 | Part 3 | Part 4 | Part 5 | Part 6 | Part 7 | Part 8 | Part 9 | Part 10 | Part 11 | Part 12 | Part 13 | Part 14 | Corrections to Part 12 & 13
Copyright 2001. Dr. James G. McCue, Jr. All rights
reserved. Postscript: And his legacy lives on in the German
Shorthaired Pointers of today. May they
always be healthy and bred with forethought and planning.
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