Genetic variability in the Sardinian population of the manila clam, Ruditapes philippinarum

摘要

The genetic variability of microsatellites was investigated among allochthonous populations of Ruditapes philippinarum (Bivalvia, Veneridae) at six sites in the Gulf of Olbia (North-East Sardinia) and one site in the Lagoon of Sacca di Goro (North Adriatic Sea). Our results demonstrate the lack of genetic substructuring of R. philippinarum populations within the Gulf of Olbia. Furthermore, we found highly similar estimates of within-population genetic variability without evidence of genetic differentiation between Sardinian and Adriatic populations. The lack of a signature of a founder effect in the Sardinian samples, notwithstanding their recent introduction, indicates that the number of R. philippinarum individuals released into the Gulf of Olbia may have been high enough to reduce the loss of genetic variability due to genetic drift. Furthermore, the absence of genetic differentiation observed between samples from the two areas suggests that the two populations belong to the same gene pool. Our results also indicated that R. philippinarum is rapidly colonizing the Gulf of Olbia and the neighboring areas, which is likely favored by its high potential for dispersal. (C) 2011 Elsevier Ltd. All rights reserved.