title: Parental exposure to environmental concentrations of diuron leads to aneuploidy in embryos of the Pacific oyster, as evidenced by fluorescent in situ hybridization.
abstract: Changes in normal chromosome numbers (i.e. aneuploidy) due to abnormal chromosome segregation may arise either spontaneously or as a result of chemical/radiation exposure, particularly during cell division. Coastal ecosystems are continuously subjected to various contaminants originating from urban, industrial and agricultural activities. Genotoxicity is common to several families of major environmental pollutants, including pesticides, which therefore represent a potential important environmental hazard for marine organisms. A previous study demonstrated the vertical transmission of DNA damage by subjecting oyster genitors to short-term exposure to the herbicide diuron at environmental concentrations during gametogenesis. In this paper, Fluorescent in situ hybridization (FISH) was used to further characterize diuron-induced DNA damage at the chromosomal level. rDNA genes (5S and 18-5.8-28S), previously mapped onto Crassostrea gigas chromosomes 4, 5 and 10, were used as probes on the interphase nuclei of embryo preparations. Our results conclusively show higher aneuploidy (hypo- or hyperdiploidy) level in embryos from diuron-exposed genitors, with damage to the three studied chromosomal regions. This study suggests that sexually developing oysters are vulnerable to diuron exposure, incurring a negative impact on reproductive success and oyster recruitment.
authors.affiliation: Ifremer, SG2M, Laboratory of Genetics and Pathology of Marine Molluscs, Avenue de Mus du Loup, 17390 La Tremblade, France; Ifremer, Department of Biogeochemistry and Ecotoxicology, Laboratory of Ecotoxicology, Rue de l'Ile d'Yeu, BP 21105, 44311 Nantes Cedex 03, France. Electronic address: audrey.barranger@ifremer.fr.
authors.forename: Audrey
authors.initials: A
authors.lastname: Barranger
authors.affiliation: Ifremer, SG2M, Laboratory of Genetics and Pathology of Marine Molluscs, Avenue de Mus du Loup, 17390 La Tremblade, France. Electronic address: abdellah.benabdelmouna@ifremer.fr.
authors.forename: Abdellah
authors.initials: A
authors.lastname: Benabdelmouna
authors.affiliation: Ifremer, SG2M, Laboratory of Genetics and Pathology of Marine Molluscs, Avenue de Mus du Loup, 17390 La Tremblade, France.
authors.forename: Lionel
authors.initials: L
authors.lastname: Dégremont
authors.affiliation: Ifremer, Department of Biogeochemistry and Ecotoxicology, Laboratory of Ecotoxicology, Rue de l'Ile d'Yeu, BP 21105, 44311 Nantes Cedex 03, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Burgeot
authors.affiliation: Ifremer, Department of Biogeochemistry and Ecotoxicology, Laboratory of Ecotoxicology, Rue de l'Ile d'Yeu, BP 21105, 44311 Nantes Cedex 03, France.
authors.forename: Farida
authors.initials: F
authors.lastname: Akcha
mesh_terms: D000782:Aneuploidy; D000818:Animals; D049896:Crassostrea / Q000187:drug effects* / Q000235:genetics*; D004249:DNA Damage / Q000187:drug effects; D004237:Diuron / Q000633:toxicity*; D004625:Embryo, Nonmammalian / Q000187:drug effects; D004781:Environmental Exposure; D005718:Gametogenesis / Q000187:drug effects; D017404:In Situ Hybridization, Fluorescence; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D014874:Water Pollutants, Chemical; D004237:Diuron
keywords: Aneuploidy; Crassostrea gigas.; Diuron; FISH