Genetic diversity and population structure of Kazakh horses (Equus caballus) inferred from mtDNA sequences.
The Kazakh horse is an important old horse breed in Xinjiang. They have contributed greatly to the breeding and improvement of other local horse breeds, yet their genetic diversity and population structure are not well understood. In the present study, we evaluated the genetic diversity of Kazakh horses and their relationship with other horse breeds using the mtDNA D-loop region, Cyt b gene, and a DNA fragment (nps 7974-9963, containing COX3, tRNA-Gly, ND3, and tRNA-Arg). A total of 130 Kazakh horses from 8 populations in China and Kazakhstan were analyzed. A total of 88 haplotypes (haplotype diversity: 0.9895) were identified, in which 3 haplotypes were shared by groups in the two countries. In a median-joining network, 6 haplogroups were found, in which most haplogroups included haplotypes from different populations. Neighbor-joining analysis revealed similar results in that haplotypes in different populations were admixed in most of the 6 clusters. In conclusion, a high level of genetic diversity was found in the Kazakh horses. However, no clear correspondence between haplogroups and geographic origin and no significant differentiation between populations in the two countries were observed. This might have resulted from the frequent contact between the two countries through the Silk Road in the past, or due to long-term outcrossing and hybridization with the introduced horses.
College of Animal Science, Tarim University, Alar, Xinjiang, China.
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Gemingguli
Department of Animal Science, Kazakhstan National Agrarian University, Almaty, The Republic of Kazakhstan.
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Iskhan
Institute of Arid Ecology and Environment, Xinjiang University, Urumqi, China.
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Y
Li
Genomics Laboratory of Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
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Qi
College of Animal Science and Veterinary, Inner Mongolia Agricultural University, Huhhot, China.
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Wunirifu
College of Animal Science, Tarim University, Alar, Xinjiang, China.
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LY
Ding
College of Animal Science, Tarim University, Alar, Xinjiang, China wumaier@tom.com.
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Wumaierjiang
D000818:Animals; D001483:Base Sequence; D001947:Breeding; D004272:DNA, Mitochondrial / Q000737:chemistry / Q000235:genetics*; D053263:Gene Regulatory Networks; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes / Q000235:genetics; D006736:Horses / Q000235:genetics*; D007623:Kazakhstan; D009690:Nucleic Acid Conformation; D010802:Phylogeny
D004272:DNA, Mitochondrial