Molecular characterisation of Bulinus snails – intermediate hosts of schistosomes in Ogun State, South-western Nigeria
Olaoluwa Akinwale 1  
,   Opeyemi Oso 2  
,   Oyetunde Salawu 3  
,   Alexander Odaibo 2  
,   Petrus Tang 4  
,   Ting-wen Chen 5  
,   Pam Gyang 1  
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Molecular Parasitology Research Laboratory, Public Health Division, Nigerian Institute of Medical Research, Lagos, Nigeria
Parasitology Research Unit, Department of Zoology, University of Ibadan, Nigeria
Department of Biosciences and Biotechnology, Babcock University, Ilishan-Remo, Nigeria
Molecular Regulation and Bioinformatics Laboratory, Department of Parasitology, College of Medicine, Chang Gung University, Taiwan
Bioinformatics Core Laboratory, Molecular Medicine Research Centre, Chang Gung University, Taiwan
Olaoluwa Akinwale   

Molecular Parasitology Research Laboratory, Public Health Division, Nigerian Institute of Medical Research, Yaba, Lagos, Nigeria
Submission date: 2014-10-28
Final revision date: 2015-02-18
Acceptance date: 2015-03-28
Publication date: 2015-05-21
Folia Malacol. 2015;23(2):137–147
Freshwater snails of the genus Bulinus O. F. Müller, 1781 are intermediate hosts for schistosomes, trematode parasites which cause schistosomiasis. The genus includes closely related species complexes with restricted gene flow between populations of each taxon. Despite their importance as intermediate hosts, unambiguous identification of these snails remains challenging. We applied molecular approach to their identification to achieve a better understanding of the epidemiology of schistosomiasis in an endemic region, south-western Nigeria. A total of 149 snails were collected and their genomic DNA was screened for schistosome infection using PCR amplification of schistosome DraI repeat sequence. The snails were identified by PCR-RFLP and/or sequencing of an amplicon of their entire ITS region including the 5.8S ribosomal RNA (rRNA) gene. Four Bulinus species, namely B. globosus (Morelet, 1866), B. forskalii (Ehrenberg, 1831), B. camerunensis Mandahl-Barth, 1957 and B. senegalensis O. F. Müller, 1781 were identified, and 34.9% (n = 52) of the 149 snails were infected: B. globosus 25.5% (n = 38), B. forskalii 5.4% (n = 8), B. camerunensis 2.7% (n = 4) and B. senegalensis 1.3% (n = 2). Restriction fragment profiles of the ribosomal ITS region for B. globosus closely matched those obtained in our previous study thus confirming the view that ribosomal ITS region of these snails could be well suited for taxonomic studies. The use of sequencing for species identification was costly and time-consuming, but it was effective in resolving true identities of snails whose restriction profiles were similar and inconclusive.
Akinwale O. P., Rollinson D., Kane R., Stothard R., Ajayi M. B., Akande D. O., Ogungbemi M. O., Duker C., Gyang P. V., Adeleke M. A. 2011. Molecular approaches to the identification of Bulinus species in South-West Nigeria and observations on natural snail infections with schistosomes. J. Helminthol. 85: 283–293.
Akogun O. B., Akogun M. K. 1996. Human behavior, water usage and schistosomiasis transmission in a small settlement near Yola, Nigeria. Ann. Trop. Med. Parasit. 90: 303–311.
Altschul S. F., Gish W., Miller W., Myers E. W., Lipman D. J. 1990. Basic local alignments search tool. J. Mol. Biol. 215: 403–410.
Betterton C., Ndifon G. T., Bassey S. E., Tan R. M., OyeyiT. 1988. Schistosomiasis in Kano State, Nigeria: human infections near dam sites and the distribution and habitat preferences of potential snail intermediate hosts. Ann. Trop. Med. Parasit. 82: 561–570.
Biocca E., Bullini L., Chabaud A., Nascetti G., Orecchia P., Paggi L. 1979. Subdivisione su base morfologica e genetica del genere Bulinus in tre ge­neri: Bulinus Muller, Physopsis Krauss e Mandahlbarthia gen. nov. Renconditi della Classe di Scienza Fisiche, Matematica e Naturali, Academia Nazionale dei Lincei seriale 8, 66: 276–282.
Brown D. S. 1994. Freshwater snails of Africa and their medical importance. 2nd ed. Taylor and Francis, London.
Ejezie G. C., Gemade E. I., Utsalo S. J. 1989. The schistosomiasis problem in Nigeria. J. Hyg. Epidemiol. Microbiol. Immunol. 33: 169–179.
Felsenstein J. 1985. Confidence limits on phylogenies: an approach using the bootstrap. Evolution 39: 783–791.
Goldman M. A., Loverde P. T., Christman C. L. 1983. Hybrid origin of polyploidy in freshwater snails of the genus Bulinus (Mollusca: Planorbidae). Evolution 37: 592–600.
Hamburger J., He N., Abbasi I., Ramzy R. M., Jourdane J., Ruppel A. 2001. Polymerase chain reaction assay based on a highly repeated sequence of Schistosoma haemato­bium: a potential tool for monitoring schistosome-infested water. Am. J. Trop. Med. Hyg. 6: 907–911.
Hotez P. J., Kamath A. 2009. Neglected tropical diseases in sub-Saharan Africa: review of their prevalence, distribution, and disease burden. Plos Negl. Trop. Dis. 3: e412.
Imevbore A. M. A., Ofozie I. E., Obot E. A. 1988. Vector-borne disease problems of small scale water resources development projects in Kano State: snail vectors of schistosomiasis. Afrancet. 1: 17–23.
Jelnes J. E. 1979. Taxonomic studies of Bulinus using isoenzyme electrophoresis with special reference to the africanus group on the Kano plain, Kenya. Malacologia 18: 147–149.
Jelnes J. E. 1986. Experimental taxonomy of Bulinus (Gastropoda: Planorbidae): the West and North African species reconsidered, based upon an electrophoretic study of several enzymes per individual. Zool. J. Linn. Soc. Lond. 87: 1–26.
Johnston D. A., Kane R. A., Rollinson D. 1993. Small subunit (18S) ribosomal RNA gene divergence in the genus Schistosoma. Parasitology 107: 147–156.
Jones C. S., Rollinson D., Mimpfoundi J., Ouma J., Kariuki H. C., Noble L. R. 2001. Molecular evolution of freshwater snail intermediate hosts within the Bulinus forskalii group. Parasitology 123: S277–S292.
Jørgensen A., Jørgensen L. V. G., Kristensen T. K., Madsen H., Stothard J. R. 2007. Molecular phylogenetic investigations of Bulinus (Gastropoda: Planorbidae) in Lake Malawi with comments on the topological incongruence between DNA loci. Zool. Scr. 36: 577–585.
Jørgensen A., Madsen H., Nalugwa A., Nyakaana S., Rollinson D., Stothard J. R., Kristensen T. K. 2011. A molecular phylogenetic analysis of Bulinus (Gastropoda: Planorbidae) with conserved nuclear genes. Zool. Scr. 40: 126–136.
Jørgensen A., Stothard J. R., Madsen H., Nalugwa A., Nyakaana S., Rollinson D. 2013. The ITS2 of the genus Bulinus: novel secondary structure among freshwater snails and potential new taxonomic markers. Acta Trop. 128: 218–225.
Kane R. A., Rollinson D. 1994. Repetitive sequences in the ribosomal DNA internal transcribed spacer of Schistosoma haematobium, Schistosoma intercalatum and Schistosoma mattheei. Mol. Biochem. Parasit. 63: 153–156.
Kane R. A., Stothard J. R., Emery A. M., Rollinson D. 2008. Molecular characterization of freshwater snails in the genus Bulinus: a role for barcodes? Parasite. Vector. 1: 15.
Mafe M. A., Von S. T., Utzinger J., N’goran E. K. 2000. Control of urinary schistosomiasis: an investigation into the effective use of questionnaires to identify high-risk communities and individuals in Niger State, Nigeria. Trop. Med. Int. Health 5: 53–63.
Mimpfoundi R., Greer J. 1989. Allozyme comparisons among species of the Bulinus forskalii group (Gastropoda: Planorbidae) in Cameroon. J. Mollus. Stud. 55: 405–410.
Nale Y., Galadima M., Yakubu S. E. 2003. Seasonal changes in the distribution and infection rate of schistosome intermediate hosts in river Kubanni and its tributaries. Biosci. Res. Comm. 15: 207–214.
Nalugwa A., Jørgensen A., Nyakaana S., Kristensen T. K. 2011. Genetic variation within and between populations of hermaphroditic Bulinus truncatus tetraploid freshwater snails of the Albertine Rift, East Africa. Hydrobiologia 673: 53–56.
Nascetti G., Bullini L. 1980. Genetic differentiation in the Mandahlbarthia truncata complex (Gastropoda: Planorbidae). Parasitology 22: 269–274.
Ndifon G. T., Ukoli F. M. A. 1989. Ecology of freshwater snails in south-western Nigeria: distribution and habitat preferences. Hydrobiology 171: 231–253.
Njiokou F., Bellec C., Jarne P., Finot L., Delay B. 1993. Mating system analysis using protein ­electrophoresis in the self-fertile hermaphrodite species Bulinus truncatus (Gastropoda: Planorbidae). J. Mollus. Stud. 59: 125–133.
Ntonifor H. N., Ajayi J. A. 2007. Studies on the ecology and distribution of some medically important freshwater snail species in Bauchi State, Nigeria. Inter. J. Biol. Chem. Sci. 1: 121–127.
Nyakaana S., Stothard J. R., Nalugwa A., Webster B. Lange C., Jørgensen A., Rollinson D., Kristensen T. K. 2013. Bulinus globosus (Planorbidae; Gastropoda) populations in the Lake Victoria basin and coastal Kenya show extreme nuclear genetic differentiation. Acta Trop. 128: 226–233.
Ofoezie I. E. 1999. Distribution of freshwater snails in the man-made Oyan Reservoir, Ogun State, Nigeria. Hydrobiology 416: 181–191.
Ofoezie I. E. 2002. Human health and sustainable water resources development in Nigeria: Schistosomiasis in artificial lakes. Natural Resources Forum 26: 150–160.
Ogbe M. G. 2002. Schistosomiasis (bilharziasis): an ancient water borne disease that occurs in some of our communities. Zoologist 1: 91–104.
Okwuosa V., Ukoli F. M. 1980. Studies on the ecology of freshwater snail vectors of schistosomiasis in south-west Nigeria: field distribution and relative abundance vis-a-vis physicochemical environmental factors. Niger. J. Parasit. 1: 87–122.
Olofintoye L. K., Odaibo A. B. 1999. Patterns of distribution and seasonality in the population dynamic of freshwater snails in river Odo-ona Ibadan, Nigeria. Biosci. Res. Comm. 1: 173–179.
Onakomaya S. O., Oyesiku K., Jegede F. J. 1992. Ogun State in Maps. 1st edn. Rex Charles Publication, Ibadan, Nigeria.
Owojori O. J., Asaolu S. O., Ofoezie I. E. 2006. Ecology of freshwater snails in Opa reservoir and research farm ponds at Obafemi Awolowo University Ile-Ife, Nigeria. J. Appl. Sci. 6: 3004–3015.
Raahauge P., Kristensen T. K. A. 2000. Comparison of Bulinus africanus group species (Planorbidae: Gastropoda) by use of the internal transcribed spacer 1 region combined by morphological and anatomical characters. Acta Trop. 75: 85–94.
Raahauge P., Rollinson D., Wright C. A. 1984. Population studies on Bulinus cernicus from Mauritius. Malacologia 25: 447–463.
Rollinson D., Kane R. A. 1991. Restriction enzyme analysis of DNA from species of Bulinus (Basommatophora: Planorbidae) using a cloned ribosomal RNA gene probe. J. Mollus. Stud. 57: 93–98.
Rollinson D., Southgate V. R. 1979. Enzyme analyses of Bulinus africanus group snails (Mollusca: Planorbidae) from Tanzania. Trans. Roy. Soc. Trop. Med. Hyg. 73: 667–672.
Rollinson D., Stothard J., Jones C. S., Lockyer A. E., De Souza C. P., Noble L. R. 1998. Molecular characterization of intermediate snail hosts and the search for resistance genes. Mem. Inst. Oswaldo Cruz 93: 111–116.
Saitou N., Nei M. 1987. The neighbor-joining method: A new method for reconstructing phylogenetic trees. Mol. Biol. Evol. 4: 406–425.
Salawu O. T., Odaibo A. B. 2014. The bionomics and diversity of freshwater snails speciesin Yewa North, Ogun State, Southwestern Nigeria. Helminthologia 51: 337–344.
Simpson A. J. G., Dame J. B., Lewis F. A., Mccutchan T. F. 1984. The arrangement of ribosomal RNA genes in Schistosoma mansoni. Identification of polymorphic structural variants. Eur. J. Biochem. 139: 41–45.
Stothard J. R., Brémond P., Andriamaro L., Sellin B., Sellin E., Rollinson D. 2001. Bulinus species on Madagascar: molecular evolution, genetic markers and compatibility with Schistosoma haematobium. Parasitology 123: 261–275.
Stothard J. R., Hughes S., Rollinson D. 1996. Variation within the internal transcribed spacer (ITS) of ribosomal DNA genes of intermediate snail hosts within the genus Bulinus (Gastropoda: Planorbidae). Acta Trop. 61: 19–29.
Stothard J. R., Mgeni A. F., Alawi K. S., Savioli L., Rollinson D. 1997. Observations on shell morphology, enzymes and random amplified polymorphic DNA (RAPD) in Bulinus africanus group snails (Gastropoda: Planorbidae) in Zanzibar. J. Mollus. Stud. 63: 489–503.
Stothard J. R., Rollinson D. 1997. Partial DNA sequences from the mitochondrial cytochrome oxidase subunit I (COI) gene can differentiate the intermediate snail hosts Bulinus globosus and B. nasutus (Gastropoda: Planorbidae). J. Nat. Hist. 31: 727–737.
Tamura K., Dudley J., Nei M., Kumar S. 2007. MEGA4: Molecular Evolutionary Genetics Analysis (MEGA) software version 4.0. Mol. Biol. Evol. 24: 1596–1599.
Tamura K., Nei M. Kumar S. 2004. Prospects for inferring very large phylogenies by using the neighbor-joining method. Proc. Nat. Acad. Sci. (USA) 101: 11030–11035.
Thompson J. D., Higgings D. G., Gibson T. J. 1994. CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position specific gap penalties and weight matrix choice. Nucleic Acids Res. 22: 4673–4680.
Zein-Eddine R., Djuikwo-Teukeng F. F., Al-Jawhari M., Senghor B., Huyse T., Dreyfuss G. 2014. Phylogeny of seven Bulinus species originating from endemic areas in three African countries, in relation to the human blood fluke Schistosoma haematobium. BMC Evol. Biol. 14: 271(1–12).
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