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Genetic relationships between Native Sheep breeds in Nigeria based on microsatellite DNA polymorphisms

Published online by Cambridge University Press:  01 August 2011

Adebambo Olufunmilayo
Affiliation:
Department of Animal Breeding & Genetics, University of Agriculture, P.M.B. 2240, Abeokuta, Nigeria
J.L. Williams
Affiliation:
Department of Animal Breeding & Genetics, University of Agriculture, P.M.B. 2240, Abeokuta, Nigeria
Sara Blott
Affiliation:
Roslin Institute, EH25 9PS Midlothian, Scotland, UK
B. Urquhart
Affiliation:
Department of Animal Breeding & Genetics, University of Agriculture, P.M.B. 2240, Abeokuta, Nigeria
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Summary

The genetic relationship among Nigeria's breeds of sheep and their crosses was studied using microsatellite DNA polymorphisms. DNA samples extracted from four Nigeria's breeds of sheep (West African Dwarf, the Balami, Uda and Yankassa) and their crosses were analysed using 30 Bovine microsatellite markers for diversity studies. Twenty of the markers were amplified by the sheep genome. Nineteen of the loci were polymorphic and were used to calculate genetic distances (Ds) between the breeds based on allele frequencies of the microsatellite. The phylogenetic relationships between the breeds were similarly estimated.

With the total number of loci studied, 285 alleles were generated and a high degree of heterozygosity was recorded (0.57 to 0.72). A relatively high degree of reliability could be placed on the tree topology with the relationship between breeds displaying a closer relationship between the Yankassa and Uda (Ds 0.356). The genetic distance was 0.432, 0.534 and 0.665 between the West African Dwarf (WAD) and the Yankassa, Uda and Balami respectively which also indicated a closer relationship between the Yankassa and the WAD compared to the essentially Northern breeds (Uda and Balami). This further confirms the evolutionary divergence of the breeds which makes them distinct entities.

The data suggests that microsatellite DNA markers are very useful tools for studying the genetic relationships among these sheep breeds. The highly polymorphic alleles could similarly be exploited in breed improvement and development.

Resumen

Se estudió la relación genética entre la raza ovina Nigeria y sus cruces utilizando microsatélite de polimorfismo de ADN. Las muestras de ADN extraídas de la raza Nigeria (West African Dwarf, Balami, Uda y Yankassa) y sus cruces, fueron analizadas utilizando 30 marcadores microsatélite bovino para el estudio de la diversidad. Veinte de estos marcadores fueron amplificados por el genoma ovino. Diecinueve de los loci fueron polimórficos y se utilizaron para calcular las distancias genéticas (Ds) entre las razas en base a la frecuencia de alelos del microsatelite. Las relaciones filogenéticas entre las razas fueron estimadas en modo similar.

Con el total de loci estudiados, se generaron 285 alelos y se anotó un elevado grado de heterocigosis (0,57 a 0,72). Podemos otorgar un cierto nivel de fiabilidad debido a la topología de los árboles junto con la relación entre las razas más cercanas como Yankassa y Uda (Ds 0,356). La distancia genética fue de 0,432, 0,534 y 0,665 entre la West African Dwarf (WAD) y la Yankassa, Uda y Balame, respectivamente; lo que también indica una relación más estrecha entre la raza Yankassa y la WAD en comparación con las razas provenientes del norte (Uda y Balami). Esto viene a confirmar ulteriormente la divergencia de evolución de las razas que hace de ellas entidades distintas.

Los datos sugieren que los marcadores microsatelites de ADN son una herramienta útil para el estudio de las relaciones genéticas entre estas razas ovinas. El elevado polimorfismo alélico puede también ser utilizado en la mejora de las razas y en su desarrollo.

Type
Research Articles
Copyright
Copyright © Food and Agriculture Organization of the United Nations 2004

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References

Bowcock, A.M., Rutz-Linares, A.. Tomfahrde, J.. Minchand, E. & Kidd, J.R.. 1994. High resolution of human evolutionary trees with polymorphic microsatellites. Nature 368: 455457.CrossRefGoogle ScholarPubMed
Cornall, R.J., Aitman, T.J., Hearne, C.M. & Todd, J.A.. 1991. The generation of a library of PCR analyses microsatellite variants for genetic mapping of the mouse genome. Genomics 10: 874881.CrossRefGoogle Scholar
Crawford, A.M., Dodds, K.G.Ede, A.J., Pierson, C.A.Montgomery, G.W.Garmonsway, H.G.Beattie, A.E.. Davies, K & Maddox, J.F.. 1995. An autosomal genetic Linkage map of the sheep genome. Genetics 140: 703724.CrossRefGoogle ScholarPubMed
Estoup, A., Piesa, P.. Krieg, F.. Vaiman, D., & Guypmard, R.. 1993. (CT) and (GT) microsatellites: a new class of genetic markers for Salmo trutta L. (Brown trout). Heredity 71: 488496.CrossRefGoogle ScholarPubMed
Forbes, S.H., Hogg, J.T.. Buchanan, F.CCrawford, A.M. & Allendorf, F.W.. 1995. Microsatellite evolution in congeneric mammals, domestic and bighorn sheep. Mol. Biol. Evol. 12: 11061113.Google ScholarPubMed
Goldstein, D.B. & Pollock, D.D.. 1994. Least Squares estimation of Molecular distance-noise abatement in phylogenetic reconstruction. Theor. Pop. Biol. 45: 219226.CrossRefGoogle ScholarPubMed
Lander, E.S. & Botstein, D.. 1989. Mapping Mendelian factors underlying quantitative traits using RFLP Linkage maps. Genetics 121: 185199.CrossRefGoogle ScholarPubMed
Litt, M. & Lutty, J.A.. 1989. A hypervariable microsatellite revealed by in vitro amplification of a dinucleotide repeat within the cardiac muscle actin gene. Ame. J.Hum. Genet 44: 397401.Google ScholarPubMed
Nei, M. 1972. Genetic distance between populations. Ame. Nat. 106: 283291.CrossRefGoogle Scholar
Nei, M. 1987. Molecular evolutionary genetics. Columbia University Press, New York.CrossRefGoogle Scholar
Nei, M., Tajima, F. & Tateno, Y.. 1983. Accuracy of estimated phylogenetic trees from molecular data. J. Mol. Evol. 19: 153170.CrossRefGoogle ScholarPubMed
Paetkau, D., Calvert, W.. Stirling, I. & Strobelle, C. 1995. Microsatellite analysis of population structure in Canadian Polar Bears. Mol. Ecol. 4: 347354.CrossRefGoogle ScholarPubMed
Ryder, M.L. 1983. Sheep and Man. Duckworth Press, London.Google Scholar
Satou, N. & Nei, M..1987. The neighbor-joining method: A new method for reconstructing phylogenetic trees. Mol. Biol. Evol. 4: 406425.Google Scholar
Tajima, F. & Takezaki, N.. 1994. Estimation of evolutionary distance for reconstructing molecular phylogenetic trees. Mol. Biol. Evol. 11: 278286.Google ScholarPubMed
Takezaki, N. & Nei, M.. 1996. Genetic distances and reconstruction of phylogenetic trees from microsatellite DNA. Genetics 144: 389399.CrossRefGoogle ScholarPubMed
Tautz, D. 1989. Hypervariability of simple sequences as general source for polymorphic DNA markers. Nucleic acid Res. 17: 64636471.CrossRefGoogle ScholarPubMed
Thaon d'Arnoldi, C., Foulley, J.L. & Ollivier, L.. 1998. An overview of the Weitzman approach to diversity. Genetics, Selection and Evolution 30: 149161.CrossRefGoogle Scholar