title: Effects of freshwater pollution on the genetics of zebra mussels (Dreissena polymorpha) at the molecular and population level.
abstract: Revealing long-term effects of contaminants on the genetic structure of organisms inhabiting polluted environments should encompass analyses at the population, molecular, and cellular level. Following this concept, we studied the genetic constitution of zebra mussel populations from a polluted (Dp) and reference sites (Cl) at the river Drava, Croatia, and applied microsatellite and DNA damage analyses (Comet assay, micronucleus test (MNT)). Additionally, mussels from both populations were exposed to polluted wastewater in the laboratory for three days, and DNA damage was analyzed to evaluate acclimatization and genetic adaptation of the investigated populations to the polluted environment. The two populations differed in their genetic constitution. Microsatellite analysis suggested that Dp had undergone a genetic bottleneck. Comet assay did not indicate any difference in DNA damage between the two populations, but MNT revealed that Dp had an increased percentage of micronuclei in hemocytes in comparison to Cl. The laboratory experiment revealed that Dp had a lower percentage of tail DNA and a higher percentage of micronuclei than Cl. These differences between populations were possibly caused by an overall decreased fitness of Dp due to genetic drift and by an enhanced DNA repair mechanism due to acclimatization to pollution in the source habitat.
authors.affiliation: Department of Ecology, Zoological Institute, University of Mainz, P.O. Box 3980, 55099 Mainz, Germany.
authors.forename: Emilia G
authors.initials: EG
authors.lastname: Thomas
authors.affiliation: Department of Zoology, Faculty of Science, University of Zagreb, Rooseveltov Trg 6, 10000 Zagreb, Croatia.
authors.forename: Maja
authors.initials: M
authors.lastname: Srut
authors.affiliation: Department of Zoology, Faculty of Science, University of Zagreb, Rooseveltov Trg 6, 10000 Zagreb, Croatia.
authors.forename: Anamaria
authors.initials: A
authors.lastname: Stambuk
authors.affiliation: Department of Zoology, Faculty of Science, University of Zagreb, Rooseveltov Trg 6, 10000 Zagreb, Croatia.
authors.forename: Göran I V
authors.initials: GI
authors.lastname: Klobučar
authors.affiliation: Department of Ecology, Zoological Institute, University of Mainz, P.O. Box 3980, 55099 Mainz, Germany.
authors.forename: Alfred
authors.initials: A
authors.lastname: Seitz
authors.affiliation: Department of Ecology, Zoological Institute, University of Mainz, P.O. Box 3980, 55099 Mainz, Germany.
authors.forename: Eva Maria
authors.initials: EM
authors.lastname: Griebeler
mesh_terms: D000818:Animals; D017523:Croatia; D004249:DNA Damage / Q000187:drug effects / Q000235:genetics*; D049875:Dreissena / Q000187:drug effects / Q000235:genetics*; D004784:Environmental Monitoring; D005618:Fresh Water; D015162:Micronucleus Tests; D014874:Water Pollutants, Chemical
chemical_list: D014874:Water Pollutants, Chemical