Genetics
Sloughi,
Saluki, Saluqi…
Genetic
Data Help Separate Semantics From Evidence
Dr.
Dominique Crapon de Caprona and Dr. Bernd Fritzsch
© Fritzsch/de
Caprona
2004
article
copyrighted with the Library of Congress 2004
do
not
use
any
parts,
sentences or pictures without written permission of
the authors.
Reproduced
with permission from Dogs in Review in which this article was first
published
(Hound Breeds Issue, July 2004)
“Oriental
Greyhounds: I. Slughi, Tazi or Gazelle hound, or Slughi Shami… II.
Ahk-Taz-eet
or Kirghiz Greyhound… III. The North African Slughi, or Slughi of
the Sahara... IV. The Barukhzy Hound, or Afghan Greyhound… V. The
Rampur
Hound, or Greyhound of Northern India… VI. The Poligar hound, or
Greyhound
of Southern India…
It
should be the object of all those who import the Greyhounds of the
East,
and breed them in this country, to try to keep distinct the different
varieties,
which in many cases have been so carefully preserved in their own
lands.
The historic interest attached to each breed is alone a sufficient
inducement
to do so.”
Amherst
F.(1907,
Oriental
Greyhounds
in
Cassell’s New Book of the dog, ed. R.Leighton
Ch.LVI, London)
Sloughi
Smooth
Saluki
~
Feathered
Saluki
Ever since sighthounds, greyhounds or Sloughis/Salukis were imported
from
their countries of origin in Asia and Africa into the western world,
numerous
myths about their origin have abounded. Clearly, except for the
Greyhound
and some smooth-coated dogs around the Mediterranean Sea, no other dog
of the 420 or so known breeds (of which the AKC recognizes less than
half)
resembles these hounds. Their swiftness and stamina, their elegant
build
and their noble attitude all contribute to the fascination these breeds
have generated among the dog fanciers in the western world.
History
shows
sighthound-like
dogs
depicted
in ancient images in the countries
of origin that resemble in many ways sighthounds still living there
today.
Consequently, some fanciers assume that indeed Salukis are ancient and
may have arisen some 2,000 or more years ago and may be the oldest
breed
of domesticated dogs. The images found in Egypt and Tepe Gawra suggest
that such smooth and coated sighthounds might be even older and date
back
to the earliest civilizations known to modern man.
Be
this
as
it
may, the checkered history of many countries in North Africa
and Southeast Asia raises certain doubts about the undisturbed
continuity
of the breeding of these hounds across such long expanses of time. In
addition,
the vast geographic area over which these sighthounds are spread,
combined
with limited accessibility in certain remote areas, raise issues of
geographic
isolation and limited genetic exchange which eventually could alter the
genetic composition of various local populations. Nevertheless, based
on
certain features, in many cases not shared with more distantly related
breeds, it seems reasonable to group all these hounds of the Orient and
North Africa into a single group with other comparatively built dogs:
the
lop-eared sighthounds of many national and international dog registries
of today (Afghan Hound, Azawakh, Saluki, Sloughi)
Among
the
various
sighthounds
found throughout Africa and the Middle East,
none has stirred more passion than the Sloughi/Saluki/Saluqi group of
hounds.
In part, the debate revolves around the name, which describes in Arabic
the local sighthound or windhound. Since in a given area only one of
those
hound types typically exists, there was no need to have more than the
generic
name that was equally used to describe the specific local variety. Of
course,
this linguistic confusion of generic and specific, combined with
various
transliterations of Arabic into European languages and the fact that
both
the colloquial “Sloughi” and the classical “Saluki” may be used to some
extent interchangeably, have confused this matter even more. This
confusion
is well summarized in Waters’ book on the Saluki ("The Saluki in
History,
Art and Sport," by Hope and David Waters, David & Charles, 1969),
and
the reader is referred to this book for more detail.
In
the
modern
era,
the
Sloughi of North Africa (henceforth simply referred
to here as Sloughi) was first imported from the French North African
colonies
to France in the 1800s. These dogs were well known in France since 1850
through the books of General Daumas and also featured at international
dog shows. Holland also was a major home of the Sloughi, brought back
at
the end of the 19th century from Africa by Auguste Le Gras.
Feathered
sighthounds were portrayed on the European continent earlier than 1700,
and were sporadically seen in the UK in the 18th century. It was around
the turn of the 20th century that serious breeding started, following
the
first imports of “Slughi Shami”to England by Lady Florence Amherst (as
she then named them) , and later on the feathered sighthounds of
Brigadier
Lance. These dogs provided the ancestors of the modern Saluki in the
West.
After
the
First
World
War ended and with the demise of the Ottoman Empire,
both the French and the British had access to the Middle East and
brought
back many Salukis (named thus in England since 1923). Surprisingly, it
appeared that the Saluki came in two varieties, a feathered variety and
a smooth variety. Logically, having a sighthound from the Middle
East that had features in common with the smooth Sloughi of North
Africa
and the smooth sighthound-like dogs painted on the murals of ancient
Egypt
raised a number of questions about the relatedness of these dogs.
Different
opinions
developed
about
this
subject over the past century and are summarized
as follows:
1)
Sloughis of North Africa and Salukis both belong to the group of
oriental
lop-eared sighthounds but are not more closely related to each other
than
the Saluki is with his eastern sighthound relatives, the Afghan Hound
or
the Tazi and Taigan of the steppe. The arguments in favor of this
scenario
assume the geographic isolation of the Sloughi in the vast expanse of
Northern
Africa and rely on the morphological differences, now also reflected to
some extent in written standards of the breeds. It assumes that the
Sloughi
and Saluki evolved in their respective countries of origin and should
be
kept distinct. We will refer to this idea as the “Sloughi hypothesis”
Fig.
1.
The
Sloughi
and
Saluki today form distinct breeds, with some potential
overlap of both breeds with each other and with other dog breeds.
2)
In contrast to this idea is the assumption that the different
geographic
varieties are tightly interconnected through interbreeding and all
Southwest
Asian and African sighthounds form a single large “breed”. The
underlying
assumption here is that western breeds known as Afghan, Saluki and
Sloughi
are artifacts of the small extracted gene pool used to found those
varieties
now registered as distinct breeds in the West, and do not reflect the
situation
in the countries of origin which show continuity in both phenotype and
the underlying genotype. We will refer to this hypothesis as the
“Saluqi
hypothesis.”
Fig.
2.
The
Sloughi/Saluki/Tazi/Afghan/Taigan
of
today are varieties of
one breed, the Saluqi, with little overlap with other dog breeds.
3)
A variation of this latter idea is the assumption that among Oriental
and
African hounds three varieties are particularly related to each other:
the smooth and feathered Salukis of the Middle East and the
smooth-coated
Sloughis and Azawakhs of Africa. This idea assumes that the African
Sloughi
and Azawakh were derived from the Saluki following the Arab invasion of
North Africa in the 7th century. We will refer to this hypothesis
as the “Saluki hypothesis.”
Fig.
3.
The
Sloughi
is
a variety of the Saluki with some potential overlap
with other breeds.
Numerous arguments have been raised over the years by proponents and
opponents
of each of these three hypotheses. With the recent completion of a
large
analysis of the mitochondrial DNA of 654 dogs of some 124 known breeds,
as well as other indigenous dog and wolf populations, the implications
of these opinions can for the first time be tested. The samples
processed
included 8 Sloughis, 15 Salukis, 6 Taigans, 1 Tazi, 10 Basenjis, and 5
Afghan Hounds.
The test consisted of sequencing an approximately 582-base-pair stretch
(* SEE FOOTNOTE) of mitochondrial DNA. This genetic material is only
inherited
through the female lines, as male sperms lose their mitochondria upon
entering
the female egg. In other words, such a study provides insights
exclusively
into the female background of a given population, no matter what the
male
looked like and what his genetic material was. Analyzing the male
genetic
background of a population requires sequencing of the male-specific
y-chromosome
that is only inherited from male to male without contribution from the
female. Such an analysis is on its way, but data are not yet available
(P. Savolainen, personal communication).
We
used the mitochondrial DNA data provided by Dr. Savolainen and looked
at
how they fit with the three ideas outlined above. We wanted to know:
1) Are
Sloughis and Salukis genetically distinct or not? Genetic
distinctness
would support the Sloughi hypothesis (Fig. 1), genetic similarity the
Saluqi
(Fig. 2) or Saluki hypothesis (Fig. 3).
2) Do
Sloughi and Saluki share genetic material with other breeds that
co-exist
in the same geographical area and potentially crossed with them in the
distant past? Are these two breeds embedded genetically into
their
geographical origin while maintaining their unique looks.
Logically,
the more genetic material is shared between these breeds and nearby
totally
different looking breeds, the less likely it is that consistent
selective
breeding took place over centuries.
3)
Are there distinct genes in Salukis and Sloughis not shared by other
breeds?
If the majority or all of the genetic sequences in a given breed are
unique,
it would indicate a long history of breeding from distinct females and
would support the hypothesis that Sloughis and Salukis are distinct
breeds.
The
Sloughi:
The
six
sequences
found
in the eight Sloughis are 50% unique to the Sloughi
and not shared by any other breeds analyzed thus far (A4, A10, A33; 2
animals,
2 animals and 1 animal respectively). Of the three sequences
shared
with other breeds, one is shared with another African breed, the
Basenji
(A5, 1 animal) but also with three breeds from Japan, Tibet and
Siberia.
Another sequence is shared with eight other breeds (A22, 1
animal):
Boxer, English Setter, Irish Wolfhound, Nguni and Sica (Africa),
Scottish
Deerhound, Saint Bernhard, and Tibetan Terrier. The last sequence
(B1, 1 animal) belongs to a different sequence group and is the only
one
shared with the Saluki, but also with 23 other known breeds, as well as
a large group of dogs from China and Indonesia. Among the breeds
are the Dachshund, Doberman Pinscher, Finnish Spitz, Pekingese, Golden
Retriever, Samoyed and Shiba (Fig. 4). These sequences are
provided
by Sloughis that maternally originated, recently or in the past, in
North
Africa, and of which some represent several well established European
and
American lines.
Dr. Savolainen and colleagues calculated that a single base
substitution
*(foot note) reflects a mutation rate of about 26,000+-8,000
years.
The three unique sequences found in Sloughis are one or more
substitutions
removed from other breeds. This suggests that the descendants of these
three lines may have stayed in North Africa for several thousand
years.
This suggestion is supported by the sequences shared with the Basenji,
the Nguni and the Sica, African breeds that are now found only south of
the Saharan desert. At the same time the geographical range of
the
other breeds who share this sequence (A5) suggests that it might be
very
old and thus widespread across Eurasia and Africa. The two other shared
sequences suggest different things. The A 22 sequence could be
related
to the invasion of North Africa by Germanic tribes in 5th-6th century
or
could simply reflect the fairly widespread distribution across Europe,
Africa and Asia of this sequence and might not be related to any
specific
historic event. The B1 sequence shared with the Saluki does not
necessarily
reflect the invasion of North Africa by the Arabs and their hounds in
the
7th century, but could be related to events long lost in the past, as
it
is shared with other widely distributed breeds of dogs. Unfortunately
this
study cannot tell us the following: was the maternal line a Sloughi or
were the mitochondria contributed by the other breeds, perhaps now
extinct?
Nor can we know the timing of these events.
These
results
strongly
support
the idea of geographic isolation with some
incorporation of three widely dispersed female sequences for the
Sloughi.
The unique sequences strongly support the notion that the Sloughi is a
genetically unique population of sighthounds and the sequences shared
with
the Basenji, Sica and Nguni indicate that this breed is, on the
maternal
side, embedded in Africa, possibly for thousands of years.
The
Saluki:
The
eight
sequences
found
in the 16 Salukis are 25% unique to the Saluki
and not shared by other breeds analyzed thus far (A43, B15, 1 animal
each).
Six sequences are shared with other breeds (Fig. 5). For example, A9 (1
animal) is shared only with the Basenji, A26 (2 animals) only with the
Wirehaired Fox Terrier of Britain, and A15 (1 animal) is shared with
the
Korean Jindo and Akbash from Turkey. The three sequences shared
with
numerous other breeds constitute about 37.5 %. B2 (7 animals), is
shared with the Afghan, the Akbash, the Canaan Dog, the Taigan and the
Tazi from Kazakstan. B1 (2 animals) is the only one shared with the
Sloughi,
but it is also shared with 23 other known breeds as well as a large
number
of dogs from China and Indonesia. A11 (1 animal) is shared with over 35
breeds (Akbash, Akita, Basset Griffon, Borzoi, Canaan Dog, Chow-Chow,
Fox
Terrier, Siberian Husky, Jindo, Kangai, Pekingese, Rottweiler, Taigan,
Thai Ridgeback, Whippet, and several dogs from China). All sequences
were
derived from Salukis out of the Middle East or bred in Europe and
America.
These
results
show
that
the genetic background of the Saluki is one of
the most complex of all breeds in this study. Clearly, the Saluki
is not a distinct population derived from a single “Saluki-Eve”. Local
Middle Eastern breeds such as Akbash and Canaan Dog appear several
times
among the Saluki’s related breeds. Whether this is because of
incorporation
of Saluki-like dogs into these breeds or vice versa remains unclear.
The
Saluki shares sequences also with the Afghan, the Taigan, the Tazi and
the Borzoi. Since these sequences are also shared by other,
non-sighthound
breeds, it is difficult to understand the direction of breeding:
a sighthound female crossed with those other breeds or a female of
those
other breeds crossed with a sighthound male. If such crosses
happened,
they may have been several thousand years ago, as the timeline of these
events can not be resolved with this study. The Afghan and Taigan share
a sequence unique to both, suggesting some, possibly ancient,
relationship,
in addition to sequences shared with several other breeds.
This
study
indicates
that
the Saluki is a local Middle Eastern breed which
has been expanded genetically by incorporation of three minor and three
major maternal lines shared with few or with many other breeds. A
single sequence is shared with the Sloughi, but is also shared with 23
other breeds and a large group of indigenous dogs from China and
Indonesia.
Therefore, this single shared sequence does not prove an affinity of
maternal
lines specific to the Sloughi. This contrasts with the more profoundly
shared maternal lines of the modern-day Saluki with local Middle
Eastern
dogs such as Akbash and Canaan Dogs, but also other Eastern sighthounds.
Saluki
~
Sloughi
The
Saluki and Sloughi compared.
These
results
reveal
that
the Sloughi breed is not integrated in the Saluki’s
gene pool, therefore cannot be derived from the Middle Eastern Hounds
brought
by the Arabs when they invaded North Africa some 1300 years ago. If
this
happened,
it
was
of such a minor scale that it had virtually no impact
on the maternal lines of the Sloughis of this study. In fact, the
three distinct maternal lines of the Sloughi suggest that those
maternal
lines might have been geographically isolated in Africa for several
thousand
years. If combined with the shared sequence with the Basenji and other
African breeds, up to 67% of the female population of the Sloughi might
have been in North Africa for a very long time.
The
results
for
the
Saluki indicate that the breed derives up to 62.5%
from possibly local females, which, however, may be common to other
local
dogs such as Akbash and Canaan Dog. The number of sequences
shared
by Saluki and Akbash is larger than those shared with any of the
geographically
nearby sighthounds, including the Sloughi. These results do not
support
the idea that the Saluki of today has been “purebred” over the last
several
thousand years and thus might be the oldest purebred dog breed, except
if we assume that such integration happened long ago. The fact
that
non-sighthound breeds such as Akbash and Canaan dog share more maternal
lines with Salukis than Salukis share with other sighthounds does not
provide
support for the Saluqi hypothesis.
To
conclude,
these
results
support
the idea that the Sloughi and Saluki of
today are distinct breeds with genetic ties to each other that are no
more
profound than those of either to many other breeds.
We
hope
that
this
essay will provide for a more rational basis of future
discussions. We deliberately refrained from quoting sources for
the
various ideas in order to allow everyone the opportunity to reconsider
those ideas in the light of these genetic results. It needs to be
stressed, however, that these conclusions are based on a limited sample
size and might undergo some revision once more samples are
included.
Nevertheless, the genetic data presented here for the first time
support
the notion previously espoused by F. Amherst and others that these
sighthound
breeds are distinct. We propose that these breeds should remain as
separate
breeds until full resolution of their genetic background is completed.
A more complete resolution of all the questions raised here will have
to
wait until the paternal side is known through analysis of the male Y
chromosome.
Finally, correlating the genetic differences described here to
differences
in phenotype will only be possible after the dog genome * (footnote) is
completed and the relationship of various genes to phenotype have been
clarified, research that will require many more years.
Acknowledgments
We
thank
Dr.
P.
Savolainen
for improving an earlier version of this manuscript.
References:
Amherst
F.
1907.
Oriental
Greyhounds.
In Cassell's New Book of the Dog, ed. R
Leighton,
pp. Ch LVI. London: Cassell & Co
Savolainen
P,
Zhang
YP,
Luo
J, Lundeberg J, Leitner T. 2002. Genetic evidence for
an East Asian origin of domestic dogs. Science 298: 1610-3
Waters
H,
Waters
D.
1969.
The Saluki in History, Art and Sport. Newton Abbot:
David & Charles. 112 pp.
Footnote
mtDNA stretch
All
genetic
information
is
built of DNA (Deoxyribonucleic acid), a giant
double helical molecule that consists of four distinct units, called
bases,
arranged in two parallel strands. These bases are A, T, C, G
(Adenine,
Thymine, Cytosine, Guanine) A interacts with T, C interacts with
G. These interactions form bridges that hold the double stranded
DNA together in a full mirror complement of each other. In essence, the
DNA is a biological digital storage system that has four signals (the
four
bases) to code for proteins.
The
genetic
information
(DNA)
of
all mammals is stored predominantly in the
nucleus of each cell. In addition, a small fraction of DNA is
also
found in mitochondria, the power plants of each cell. This
mitochondrial
DNA (mtDNA) is only inherited from the female to her offspring.
No
male mtDNA contributes to the next generation. Therefore each
male
is a dead end with respect to inheritance of mtDNA information.
Analyzing
the sequence of mtDNA provides thus exclusive information only about
the
mother’s side of a given dog. Only information about the mother,
grandmother, great grandmother etc of a dog will be revealed.
Since
mtDNA, like any other DNA, encodes information in the arrangement of
the
four bases, one can compare the arrangements of these four bases to
study
similarities of animals that result from common inheritance.
Thus,
sequencing a stretch or segment of the mtDNA will provide genetic
information
about the inherited relatedness of dogs. Such an analysis would
be
comparable to ordering all of the letters on this page into a single
line
without any interruptions and comparing this with files similarly
obtained
of pages from other books. Logically, only faithful copies of the
page would show a high resemblance in the sequence of letters over such
a long stretch.
Base
substitution.
Altering
the
information
encoded
in the orderly arrangement of bases on
the DNA requires altering the sequence of bases. Such an
alteration
is called a mutation. Such mutations can do a number of
things.
In many cases, mutations change a single base. Thus, instead of
an
A it will substitute that for a G, for example. Such base
alteration
rates typically range in the order of several hundreds or thousands of
years, depending on the sequence in question.
Dog
genome.
The
genome
is
all
the inherited information or DNA carried from one
generation
to the next in a given being. The genome of four mammals has thus
far been sequenced, humans, mice, rats and dogs. A comparison
revealed
that dogs and humans share approximately 90% of their genes.
ABOUT DR.
BERND FRITZSCH
ABOUT
DR.
DOMINIQUE
DE
CAPRONA
|