Differentiation among Spanish sheep breeds using microsatellites [population assignement, individual clustering analysis]

• Published in: Genetics selection evolution (Paris) Vol. 33; no. 5; pp. 529 - 542
• Main Authors: Arranz, J.J. ((Universidad de Leon (Espagne). Departamento de Produccion Animal)), Bayon, Y, San Primitivo, F
• Format: Journal Article
• Language: English
• Published: Les Ulis EDP Sciences 01.09.2001; BioMed Central Ltd; BioMed Central; BMC
• Subjects: ADN; Alleles; AMELIORATION DES ANIMAUX; ANIMAL BREEDING; Animal productions; Animals; Bayes Theorem; Bayesian statistical decision theory; Biological and medical sciences; BREEDS (ANIMALS); Cluster Analysis; DNA; ESPAGNE; ESPANA; Fundamental and applied biological sciences. Psychology; Genetic aspects; Genetic Variation; GENETICA MOLECULAR; Genetics of eukaryotes. Biological and molecular evolution; GENETIQUE MOLECULAIRE; Heterozygote; individual clustering analysis; MEJORAMIENTO ANIMAL; Methods; Microsatellite Repeats - genetics; microsatellites; MOLECULAR GENETICS; OVIN; OVINOS; Ovis; Physiological aspects; POLIMORFISMO; POLYMORPHISM; POLYMORPHISME; population assignment; Population genetics, reproduction patterns; RACE (ANIMAL); RAZAS (ANIMALES); Satellite DNA; SHEEP; Sheep - genetics; sheep breeds; SPAIN; Terrestrial animal productions; Vertebrata; Vertebrates; Europe; Spain; Cluster analysis; Farming animal; Genetic variability; Ruminant animal; BREEDS (ANIMALS); Experimental study; Population genetics; Vertebrata; Mammalia; Microsatellite DNA; Genetic identification; Sheep; Artiodactyla; Ungulata
• ISSN: 0999-193X; 1297-9686; 1297-9686
• DOI: 10.1186/1297-9686-33-5-529

Genetic variability at 18 microsatellites was analysed on the basis of individual genotypes in five Spanish breeds of sheep - Churra, Latxa, Castellana, Rasa-Aragonesa and Merino -, with Awassi also being studied as a reference breed. The degree of population subdivision calculated between Spanish breeds from FST diversity indices was around 7/ of total variability. A high degree of reliability was obtained for individual-breed assignment from the 18 loci by using different approaches among which the Bayesian method provided to be the most efficient, with an accuracy for nine microsatellites of over 99/. Analysis of the Bayesian assignment criterion illustrated the divergence between any one breed and the others, which was highest for Awassi sheep, while no great differences were evident among the Spanish breeds. Relationships between individuals were analysed from the proportion of shared alleles. The resulting dendrogram showed a remarkable breed structure, with the highest level of clustering among members of the Spanish breeds in Latxa and the lowest in Merino sheep, the latter breed exhibiting a peculiar pattern of clustering, with animals grouped into several closely set nodes. Analysis of individual genotypes provided valuable information for understanding intraand inter-population genetic differences and allowed for a discussion with previously reported results using populations as taxonomic units