title: Reduced susceptibility of a Biomphalaria tenagophila population to Schistosoma mansoni after introducing the resistant Taim/RS strain of B. tenagophila into Herivelton Martins stream.
abstract: Studies performed in the last 30 years demonstrated that a strain of B. tenagophila from the Taim Biological Reserve is completely resistant to Schistosoma mansoni infection. This resistance to parasite infection is a dominant characteristic during crossbreeding with susceptible B. tenagophila strains. These experiments also identified a 350 bp molecular marker that is exclusive to the Taim strain and does not occur in other geographic strains of this snail species. The Taim strain (Taim/RS) of Biomphalaria tenagophila was bred on a large scale, physically marked and introduced into a stream in which previous malacological analyses had revealed the presence of only parasite-susceptible B. tenagophila. Samples of offspring captured 4, 11 and 14 months after the introduction of the Taim strain were examined, and the susceptibility of the snails to S. mansoni infection dropped from 38.6-26.5% to 2.1% during the 14 months after the introduction of the Taim snail strain. A significant correlation was also observed between the absence of infection and the identification of the Taim molecular marker. These results demonstrate that the genetic marker from the Taim strain was successfully introduced into the wild snail population. In addition, a significant relationship exists between the marker and resistance to infection.
authors.affiliation: Laboratory of Schistosomiasis, Research Center René Rachou/FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Daisymara Priscila de Almeida
authors.initials: DP
authors.lastname: Marques
authors.affiliation: Laboratory of Parasitology, Institute of Biological Sciences, Federal University of Juiz de Fora, São Pedro, Minas Gerais, Brazil.
authors.forename: Florence Mara
authors.initials: FM
authors.lastname: Rosa
authors.affiliation: Chácara Santa Inês, Bananal, São Paulo, Brazil.
authors.forename: Engels
authors.initials: E
authors.lastname: Maciel
authors.affiliation: Laboratory of Schistosomiasis, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Deborah
authors.initials: D
authors.lastname: Negrão-Corrêa
authors.affiliation: Superintendência de Controle de Endemias do Estado de São Paulo/SUCEN, São Paulo, Brazil.
authors.forename: Horácio Manuel Santana
authors.initials: HM
authors.lastname: Teles
authors.affiliation: Laboratory of Helminthology and Medical Malacology, Research Center René Rachou/FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Roberta Lima
authors.initials: RL
authors.lastname: Caldeira
authors.affiliation: Mollusk Room Dr. Lobato Paraense, Research Center René Rachou/FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Liana Konovaloff
authors.initials: LK
authors.lastname: Jannotti-Passos
authors.affiliation: Laboratory of Schistosomiasis, Research Center René Rachou/FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Paulo Marcos Zech
authors.initials: PM
authors.lastname: Coelho
mesh_terms: D000818:Animals; D020029:Base Pairing; D001700:Biomphalaria / Q000469:parasitology*; D001938:Brazil; D004198:Disease Susceptibility; D004591:Electrophoresis, Polyacrylamide Gel; D005819:Genetic Markers; D012150:Polymorphism, Restriction Fragment Length; D011156:Population Density; D045483:Rivers; D012550:Schistosoma mansoni / Q000502:physiology*; D012555:Schistosomiasis mansoni / Q000469:parasitology*; D016622:Silver Staining
chemical_list: D005819:Genetic Markers