The genetic structure of Mytilus chilensis (Hupe 1854) populations along the Chilean coast based on RAPDs analysis

Abstract

The Chilean blue mussel Mytilus chilensis is an important commercial species. However, little has been published on the population genetics of this species, despite the need to implement management and conservation policies. Randomly amplified polymorphic DNA‐polymerase chain reaction analysis was used to estimate genetic variation within and between eight natural populations along the whole range of its Chilean natural distribution (ca. 1900 km from Arauco (VIII Region) to Punta Arenas (XII Region)). The values of Nei's unbiased genetic distance, D (0.030–0.107), among populations were small, despite the large geographic separation. A mantel test using 50 000 randomizations showed evidence for a significant correlation (r=0.74, P<0.05) between genetic and geographic (coastal) distance. Punta Arenas population was the most genetically differentiated from the others, although the scale of differentiation was not large (D=0.076–0.107). The levels of gene flow (Nm=1.55) found in this study prevent differentiation among populations by genetic drift. This is the result of the long‐lived planktotrophic larvae of M. chilensis, which provides this species with considerable dispersal ability throughout its range, which is favoured by the ocean currents along the Chilean coast. A restricted larval dispersal towards the north due to the Cape Horn Current derived from the West Wind Drift could be the cause of the higher genetic differentiation of Punta Arenas population from the northern populations. For management purposes of the M. chilensis fishery, the results provide no evidence for discrete stocks, with the possible exception of the Punta Arenas population. The present study provides the baseline data in order to continue further characterization of these mussel populations, considering the great increase in aquaculture of this species.

Genetic characterization and evaluation of anthropogenic impacts on genetic patterns in cultured and wild populations of mussels (Mytilus galloprovincialis) from Greece

“…Such results are common in Mytilus species and have been reported in a number of studies, including those for populations of M. chilensis along Chilean coasts using RAPD markers (Toro et al, 2004) and for M. californianus from Californian coasts using allozyme, mtDNA, and single-copy nuclear DNA markers (Addison et al, 2008).…”

Strong genetic differentiation among east Atlantic populations of the sword razor shell (Ensis siliqua) assessed with mtDNA and RAPD markers

“…Among them, RAPDs (Welsh and McClelland 1990) allow a fast and convenient way to unravel the genetic diversity in species without a previous knowledge of the genome and have been extensively used to evaluate the population structure in molluscs (e.g. Huang et al 2000;Holmes et al 2003;Toro et al 2004;Casu et al 2005;Barreiro et al 2006;Holmes and Miller 2006). Similarly, the analysis of mitochondrial DNA has been useful in determining the genetic population structure of molluscan species (e.g.…”

Supernumerary chromosomes on Southern European populations of the cockle Cerastoderma edule: Consequence of environmental pollution?

“…The discrepancy of the percentage of hyperdiploid cells ob-served between the Ria Formosa population with 15% and the 3 Galician populations with 35%, 37% and 43% could probably be due to: (a) interpopulation genetic variability among the different Cerastoderma edule populations, as found for instance, in different populations geographically distant of Pecten maximus (Heipel et al, 1998), Haliotis rubra (Huang et al, 2000) and Mytilus chilensis (Toro et al, 2004); (b) to the impact of different environmental conditions to which these populations have been subjected. There are not presently any comparative studies on population genetics in C. edule.…”