DNA Suggests Beginnings of Basenji Breed
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Course #103 Basenji Timeline Basenji University “Preserving Our Past and Educating Our Future” DNA Suggests Beginnings of Basenji Breed Quotes from this paper which appeared in SCIENCE, 21 May 2004 VOL 304 www.sciencemag.org Genetic Structure of the Purebred Domestic Dog Heidi G. Parker,1,2,3 Lisa V. Kim,1,2,4 Nathan B. Sutter,1,2 Scott Carlson,1 Travis D. Lorentzen,1,2 Tiffany B. Malek,1,3 Gary S. Johnson,5 Hawkins B. DeFrance,1,2 Elaine A. Ostrander,1,2,3,4* Leonid Kruglyak1,3,4,6 We used molecular markers to study genetic … relationships in a diverse collection of 85 domestic The domestic dog is a genetic enterprise dog breeds. Differences among breeds accounted unique in human history. No other mammal has for (30% of genetic variation. Microsatellite enjoyed such a close association with humans genotypes were used to correctly assign 99% of over so many centuries, nor been so substantially individual dogs to breeds. Phylogenetic analysis shaped as a result. A variety of dog morphologies separated several breeds with ancient origins from have existed for millennia and reproductive the remaining breeds with modern European isolation between them was formalized with the origins. We identified four genetic clusters, which advent of breed clubs and breed standards in the predominantly contained breeds with similar mid–19th century. Since that time, the geographic origin, morphology, or role in human promulgation of the “breed barrier” rule—no dog activities. These results provide a genetic may become a registered member of a breed classification of dog unless both its dam and sire are registered Basenji University #103 Basenji Timeline 1 members —has ensured a relatively closed genetic separated the Basenji, an ancient African breed. pool among dogs of each breed. At present, there The third split separated two Arctic spitz-type are more than 400 described breeds, 152 of which breeds, the Alaskan Malamute and Siberian are recognized by the American Kennel Club Husky, and the fourth split separated two Middle (AKC) in the United States (1). Eastern sight hounds, the Afghan and Saluki, from … the remaining breeds. Having demonstrated that modern dog … breeds are distinct genetic units, we next sought to At first glance, it is surprising that a single define broader genetic relationships among the genetic cluster includes breeds from Central Africa breeds. We first used standard neighbor-joining (Basenji), the Middle East (Saluki and Afghan), methods to build a majority-rule consensus tree of Tibet (Tibetan Terrier and Lhasa Apso), China breeds (Fig. 2), with distances calculated using the (Chow Chow, Pekingese, Shar-Pei, and Shi Tzu), chord distance measure (26), which does not Japan (Akita and Shiba Inu), and the Arctic assume a particular mutation model and is thought (Alaskan Malamute, Siberian Husky, and to perform well for closely related taxa (27). The Samoyed). However, several researchers have tree was rooted using wolf samples. The deepest hypothesized that early pariah dogs originated in split in the tree separated four Asian spitz-type Asia and migrated with nomadic human groups breeds, and within this branch the Shar-Pei split both south to Africa and north to the Arctic, with first, followed by the Shiba Inu, with the Akita and subsequent migrations occurring throughout Asia Chow Chow grouping together. The second split (5, 6, 30). Basenji University #103 Basenji Timeline 2 New Genetic Study Gives Nod to Basenjis as One of Few Remaining Ancient Breeds This review of the article was written by Karla Schreiber A recent study by top canine and human other breed by virtue of current canine DNA geneticists* supports the premise that Basenji testing. fanciers have believed for many years: Our dogs are different from most other breeds, and have a Of greatest interest to Basenji fanciers, the unique and ancient genetic origin that is revealed study also compared the DNA of purebred dogs through a careful study of canine DNA. (including Basenjis) to an amalgam of DNA samples of eight gray wolves from China, Oman, The study, published in May, 2004, Iran, Sweden, Italy, Mexico, Canada and the compared the DNA of eighty-five purebred dogs to United States in an effort to determine which one another, and determined that contrary to prior breeds are most highly related, genetically, to belief, individual members of each breed cluster existing wild canids. The results of this aspect of together in the vast majority of instances. Modern the study were surprising. The breeds with DNA breeds are, per the study, more genetically distinct most identical to the wolf DNA are Shar-Peis, than previously believed. In fact, the degree of Shiba Inu, Akita, and Chow Chow. These four genetic diversity across all breeds included in the breeds clustered together and are genetically study was as great as the genetic diversity of the similar. The next “break out” breed was the human population as a whole. However, genetic BASENJI, standing alone. Following the Basenji, diversity within breeds is very limited due to closed are the Alaskan Malamute and the Siberian Husky, gene pools, or what the study calls “the breed clustered together, followed by the Afghan and barrier rule” – which discourages out-crossing Saluki, clustered together. Other ancient breeds, between breeds. As a result of years of inbreeding according to the study, included the Samoyed, on common ancestors, most breeds existing today Tibetan Terrier, Lhasa Apso and Pekingese can be specifically identified as distinct from any Basenji University #103 Basenji Timeline 3 All other breeds included in the study are to Africa and north to the Arctic, with subsequent significantly different, genetically, from these migrations throughout Asia.” “ancient” breeds, and are more similar to one another than to any of the breeds with DNA more The study also provided some startling closely resembled wolf DNA. information about breeds that, until now, have been considered ancient – the Pharaoh Hound, A quote from the study puts these findings Ibizan Hound and Norwegian Elkhound. DNA into perspective: analysis does not support this conclusion. These breeds have been “… recreated in more recent “A subset of breeds with ancient Asian and times from combinations of other breeds. Thus, African origins splits off from the rest of the breeds although their appearance matches the ancient and shows shared patterns of allele (genetic) (hounds), their genomes do not.” frequency. At first glance, it is surprising that a single genetic cluster includes breeds from Central As Basenji fanciers have known from the Africa (Basenji), the Middle East (Saluki and outset, our little native African dogs are ancient Afghan), Tibet (Tibetan Terrier and Lhasa Apso), and unique – and now the science of genetics China (Chow Chow, Pekingese, Shar Pei), Japan shows us just how ancient and unique they are. It (Akita and Shiba Inu) and the Arctic (Alaskan is a privilege and a challenge to act as guardians Malamute, Siberian Husky and Samoyed). of an ancient breed – a breed that pre-dates the However, several researchers have hypothesized vast majority of “purebred dogs” and harkens back that early pariah dogs originated in Asia and to the earliest years of human civilization. And with migrated with nomadic human groups both south that privilege and challenge, comes increased responsibility, for breeders and owners alike. *Genetic Structure of the Purebred Domestic Dog, Science, Vol. 304, Issue 5674, 1160-1164, 21 May 2004, by H. Parker, L. Kim, N. Sutter, S. Carlson, T. Lorentzen, T. Malek, G. Johnson, H. DeFrance, E. Ostrander, and L. Kruglyak. **Read the Science article in its entirety at: http://www.akcchf.org/news/press/releases/2004/dogbreeds.pdf Basenji University #103 Basenji Timeline 4 .