Study of Biomphalaria Tenagophila Tenagophila, B. t. Guaibensis and B. Occidentalis by Polymerase Chain Reaction Amplification and Restriction Enzyme Digestion of the Ribosomal RNA Intergenic Spacer Regions

Biomphalaria tenagophila tenagophila, B. tenago phila guaibensis and B. occidentalis are indistinguishable on the basis of shell morphology and the majority of organs of the genital system. Only B. t. tenagophila is susceptible to infection with Schisto soma mansoni. The identification of this species is important for epidemiological studies of schistosomiasis. Snails from different sites in Brazil, Argentine and Uruguay were studied using the Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP) of the Ribosomal RNA Internal Transcribed Spacers (ITS) using seven enzymes. Profiles resulting from digestion with AluI showed some invariant species-specific products allowing correct identification of B. t. tenagophila, B. occidentalis and B. t. guaibensis . Profiles obtained with other enzymes did not permit species identification as extensive intraspecific polymorphism or invariant RFLP profiles were observed. Restriction profiles obtained with all enzymes were used to calculate the percentage of band sharing between all individual snails and these data were used for a cluster analysis. A closer relationship between B. occidentalis and B. t. guaibensis than B. t. tenagophila and the subspecies B. t. guaibensis was observed. Based on previous morphological data and these molecular data, we propose grouping B. t. tenago phila, B. occidentalis and B. t. guaibensis into a B. tenagophila complex.

[1]  A. Simpson,et al.  Biomphalaria spp: identification of the intermediate snail hosts of Schistosoma mansoni by polymerase chain reaction amplification and restriction enzyme digestion of the ribosomal RNA gene intergenic spacer. , 1998, Experimental parasitology.

[2]  D. Blair,et al.  Relationships among problematic North American stagnicoline snails (Pulmonata: Lymnaeidae) reinvestigated using nuclear ribosomal DNA internal transcribed spacer sequences , 1997 .

[3]  D. Rollinson,et al.  Molecular characterization of Bulinus globosus and B. nasutus on Zanzibar, and an investigation of their roles in the epidemiology of Schistosoma haematobium. , 1997, Transactions of the Royal Society of Tropical Medicine and Hygiene.

[4]  C. O. Cunningham,et al.  Species variation within the internal transcribed spacer (ITS) region of Gyrodactylus (Monogenea:Gyrodactylidae) ribosomal RNA genes. , 1997, The Journal of parasitology.

[5]  R. Speare,et al.  Genetic markers in ribosomal DNA for hookworm identification. , 1996, Acta tropica.

[6]  D. Rollinson,et al.  Variation within the internal transcribed spacer (ITS) of ribosomal DNA genes of intermediate snail hosts within the genus Bulinus (Gastropoda: Planorbidae). , 1996, Acta tropica.

[7]  A. Simpson,et al.  Rapid silver staining and recovery of PCR products separated on polyacrylamide gels. , 1994, BioTechniques.

[8]  A. Simpson,et al.  Biomphalaria glabrata: extensive genetic variation in Brazilian isolates revealed by random amplified polymorphic DNA analysis. , 1994, Experimental parasitology.

[9]  D. McManus,et al.  Genetic variation in geographically isolated populations and subspecies of Oncomelania hupensis determined by a PCR-based RFLP method. , 1994, Acta tropica.

[10]  V. Barral,et al.  Detection of genetic diversity within snail intermediate hosts of the genus Bulinus by using random amplified polymorphic DNA markers (RAPDs). , 1993, Acta tropica.

[11]  A. Simpson,et al.  Sex determination by low stringency PCR (LS-PCR). , 1993, Nucleic acids research.

[12]  P. Brindley,et al.  Schistosoma mansoni: use of a cloned ribosomal RNA gene probe to detect restriction fragment length polymorphisms in the intermediate host Biomphalaria glabrata. , 1991, Experimental parasitology.

[13]  W. L. Paraense,et al.  Probable extension of schistosomiasis mansoni to southernmost Brazil. , 1987, Memorias do Instituto Oswaldo Cruz.

[14]  J. Jelnes Experimental taxonomy of Bulinus (Gastropoda: Planorbidae): the West and North African species reconsidered, based upon an electrophoretic study of several enzymes per individual , 1986 .

[15]  W. L. Paraense Biomphalaria Tenagophila Guaibensis ssp. n. from Southern Brazil and Uruguay (pulmonata: Planorbidae). I. Morphology , 1984 .

[16]  J. Jelnes Experimental taxonomy of Bulinus (gastropoda: planorbidae) , 1979 .

[17]  W. L. Paraense,et al.  Observations on the morphology of Australorbis nigricans. , 1955, Memorias do Instituto Oswaldo Cruz.

[18]  L. R. Dice Measures of the Amount of Ecologic Association Between Species , 1945 .

[19]  A. Simpson,et al.  SPECIFIC IDENTIFICATION OF BIOMPHALARIA TENAGOPHILA AND BIOMPHALARIA OCCIDENTALIS POPULATIONS BY THE LOW STRINGENCY POLYMERASE CHAIN REACTION , 1997 .

[20]  D. Rollinson,et al.  Repetitive sequences in the ribosomal DNA internal transcribed spacer of Schistosoma haematobium, Schistosoma intercalatum and Schistosoma mattheei. , 1994, Molecular and biochemical parasitology.

[21]  W. L. Paraense Biomphalaria occidentalis sp. n. from South America (Mollusca Basommatophora Pulmonata). , 1981, Memorias do Instituto Oswaldo Cruz.

[22]  Ernst Mayr,et al.  Principles of systematic zoology , 1969 .

[23]  P. Sneath,et al.  Numerical Taxonomy , 1962, Nature.