Differentiation among Spanish sheep breeds using microsatellites

Genetics Selection Evolution

Fermín San Primitivo¹  Yolanda Bayón¹  Juan-José Arranz¹ 

[1] Departamento de Producción Animal, Universidad de León, 24071 León, Spain

关键词: individual clustering analysis;    population assignment;    sheep breeds;    microsatellites;   

Others  :  1094635
DOI  :  10.1186/1297-9686-33-5-529

 received in 2000-11-02, accepted in 2001-04-23,  发布年份 2001

【 摘 要 】

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 F_ST 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 intra- and inter-population genetic differences and allowed for a discussion with previously reported results using populations as taxonomic units.

【 授权许可】

   
2001 INRA, EDP Sciences