Heterologous microsatellite-based genetic diversity in blue mussel y diferenciacion entre localidades del sur de Chile usando marcadores microsatelites heterologos

• Published in: Latin american journal of aquatic research 2015-11, Vol.43 (5), p.998
• Main Authors: Larrain, Maria Angelica, Diaz, Nelson F, Lamas, Carmen, Uribe, Carla, Jilberto, Felipe, Araneda, Cristian
• Format: Article
• Language: Spanish
• ISSN: 0718-560X; 0718-560X
• DOI: 10.3856/vol43-issue5-fulltext-20

Mussels (Mytilus spp.) are one of the most cultivated and commercialized bivalves in southern Chile; culture is currently supplied almost entirely from wild-caught seed obtained from relatively few collection centers. The genetic diversity and differentiation of the blue mussel in southern Chile was investigated by sampling six locations: one natural bank and five seed collection centers. Nine polymorphic microsatellite (SSR) loci were genotyped (Mgul, Mgu3, MT203, MT282, Mg15, Mg56, Med737, MIT02 andMGE005). We found 75 different alleles, six of which were private alleles. Of the analyzed loci, 45 of 54 tests performed deviated from Hardy-Weinberg equilibrium after sequential Bonferroni correction (P < 0.05), revealing significant heterozygote deficiencies. The polymorphic information content (PIC) ranged from 0.322 (MGE005) to 0.893 (Mgu1). Despite the long distance between some sampling sites (up to 1360 km), genetic differentiation among the sites was low ([F.sub.ST] = 0.043, P < 0.0001). The Bayesian cluster analysis (STRUCTURE) indicated two probable clusters, while the non-parametric cluster analysis (AWclust) identified two to four clusters. Both analyses showed a high level of admixture within clusters. Our results indicate that blue mussels in southern Chile show lower genetic diversity than in other countries, low inbreeding levels, and limited genetic differentiation among locations. Keywords: Mytilus, mussels, genetic diversity, genetic differentiation, microsatellites, southern Chile. Los mejillones (Mytilus spp.) constituyen unos de los bivalvos mas cultivados y comercializados en el sur de Chile. Su cultivo esta actualmente abastecido completamente con semillas obtenidas desde el medio natural, de relativamente pocos centros de captacion. La diversidad y diferenciacion genetica de los mejillones en el sur de Chile fue investigada muestreando seis lugares, un banco natural y cinco centros de captacion de semilla. Se genotiparon nueve loci microsatelite (SSR) polimorficos (Mgu1, Mgu3, MT203, MT282, Mg15, Mg56, Med737, MIT02 y MGE005). Se encontraron 75 alelos diferentes, seis de ellos fueron alelos privados. En los loci analizados, 45 de los 54 test realizados mostraron desviacion significativa (P < 0,05) del equilibrio de Hardy-Weinberg despues de la correccion secuencial de Bonferroni, revelando un significativo deficit de heterocigotos. El contenido de informacion polimorfica (PIC) vario entre 0,322 (MGE005) y 0,893 (Mgu1). A pesar de la g