title: Genetic diversity and molecular detection of three toxic dinoflagellate genera (Alexandrium, Dinophysis, and Karenia) from French coasts.
abstract: The objectives of this study were 1) to study the genetic diversity of the Alexandrium, Dinophysis and Karenia genera along the French coasts in order to design probes targeting specific DNA regions, and 2) to apply PCR-based detection to detect these three toxic dinoflagellate genera in natural samples. Genetic diversity of these toxic taxa was first studied from either cultures or cells isolated from Lugol-fixed field samples. By this way, partial sequences of the large ribosomal subunit (LSU rDNA) including the variable domains D1 and D2 of A. minutum, Alexandrium species inside the tamarensis complex, the D. acuminata complex and K. mikimotoi were obtained. Next, specific primers were designed for a selection of toxic algae and used during semi-nested PCR detection. This method was tested over a 3-month period on water samples from the Bay of Concarneau (Brittany, France) and on sediment from the Antifer harbor (The English Channel, France). Specificity and sensitivity of this molecular detection were evaluated using the occurrence of target taxa reported by the IFREMER (Institut Français de Recherche pour l'Exploitation de la Mer) monitoring network based on conventional microscopic examination. This work presents the first results obtained on the biogeographical distribution of genotypes of these three toxic genera along the French coasts.
authors.affiliation: IFREMER, Centre de Brest, DRVNP/CMM, Plouzané, France. lguillou@icm.csic.es
authors.forename: Laure
authors.initials: L
authors.lastname: Guillou
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Nézan
authors.forename: Valérie
authors.initials: V
authors.lastname: Cueff
authors.forename: Evelyne
authors.initials: E
authors.lastname: Erard-Le Denn
authors.forename: Marie-Anne
authors.initials: MA
authors.lastname: Cambon-Bonavita
authors.forename: Patrick
authors.initials: P
authors.lastname: Gentien
authors.forename: Georges
authors.initials: G
authors.lastname: Barbier
mesh_terms: D000818:Animals; D017931:DNA Primers; D016054:DNA, Protozoan / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification; D004275:DNA, Ribosomal / Q000235:genetics; D004141:Dinoflagellida / Q000145:classification / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification*; D005602:France; D014644:Genetic Variation; D008387:Marine Toxins / Q000032:analysis / Q000235:genetics; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D012623:Seawater / Q000382:microbiology*; D012680:Sensitivity and Specificity
chemical_list: D017931:DNA Primers; D016054:DNA, Protozoan; D004275:DNA, Ribosomal; D008387:Marine Toxins