title: Biomphalaria tenagophila: dominant character of the resistance to Schistosoma mansoni in descendants of crossbreedings between resistant (Taim, RS) and susceptible (Joinville, SC) strains.
abstract: The aim of the present work was to study parasitological, molecular, and genetic aspects in descendants of crossbreedings between a totally resistant Biomphalaria tenagophila strain (Taim, RS) and another one highly susceptible (Joinville, SC) to Schistosoma mansoni. Descendants F1 and F2 were submitted to S. mansoni infection (LE strain). The susceptibility rates for individuals from Group F1 were 0 to 0.6%, and from Group F2 was 7.2%. The susceptible individuals from Group F2 discharged a lower number of cercariae, when compared with the susceptible parental group, and in 2 out of 9 positive snails the cercarial elimination was discontinued. In order to identify genetic markers associated with resistance the genotype of parental snails and their offspring F1 and F2 were analyzed by means of the randomly amplified polymorphic DNA method. Nevertheless, it was not possible to detect any marker associated to resistance, but the results showed that in the mentioned species the resistance character is determined by two dominant genes.
authors.affiliation: Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Florence Mara
authors.initials: FM
authors.lastname: Rosa
authors.forename: Ana Lúcia Brunialti
authors.initials: AL
authors.lastname: Godard
authors.forename: Vasco
authors.initials: V
authors.lastname: Azevedo
authors.forename: Paulo Marcos Zech
authors.initials: PM
authors.lastname: Coelho
mesh_terms: D000818:Animals; D001700:Biomphalaria / Q000235:genetics* / Q000469:parasitology; D001947:Breeding / Q000379:methods*; D003433:Crosses, Genetic; D005799:Genes, Dominant / Q000235:genetics*; D005819:Genetic Markers; D006790:Host-Parasite Interactions / Q000235:genetics; D019105:Random Amplified Polymorphic DNA Technique; D012550:Schistosoma mansoni / Q000502:physiology*
chemical_list: D005819:Genetic Markers