Detecting hybridization in African schistosome species; does egg morphology complement molecular species identification?

Nele A M Boon, Wouter Fannes, Sara Rombouts, Katja Polman, Filip A M Volckaert, Tine Huyse

    Research output: Contribution to journalA1: Web of Science-articlepeer-review

    45 Downloads (Pure)


    Hybrid parasites may have an increased transmission potential and higher virulence compared to their parental species. Consequently, hybrid detection is critical for disease control. Previous crossing experiments showed that hybrid schistosome eggs have distinct morphotypes. We therefore compared the performance of egg morphology with molecular markers with regard to detecting hybridization in schistosomes. We studied the morphology of 303 terminal-spined eggs, originating from 19 individuals inhabiting a hybrid zone with natural crosses between the human parasite Schistosoma haematobium and the livestock parasite Schistosoma bovis in Senegal. The egg sizes showed a high variability and ranged between 92·4 and 176·4 µm in length and between 35·7 and 93·0 µm in width. No distinct morphotypes were found and all eggs resembled, to varying extent, the typical S. haematobium egg type. However, molecular analyses on the same eggs clearly showed the presence of two distinct partial mitochondrial cox1 profiles, namely S. bovis and S. haematobium, and only a single nuclear ITS rDNA profile (S. haematobium). Therefore, in these particular crosses, egg morphology appears not a good indicator of hybrid ancestry. We conclude by discussing strengths and limitations of molecular methods to detect hybrids in the context of high-throughput screening of field samples.

    Original languageEnglish
    Issue number7
    Pages (from-to)954-964
    Number of pages11
    Publication statusPublished - 2017


    • Adolescent
    • Animals
    • Child
    • Child, Preschool
    • DNA, Helminth/genetics
    • DNA, Ribosomal Spacer/genetics
    • Electron Transport Complex IV/genetics
    • Female
    • Helminth Proteins/genetics
    • Humans
    • Hybridization, Genetic
    • Male
    • Mitochondrial Proteins/genetics
    • Ovum/cytology
    • Schistosoma/classification
    • Schistosoma haematobium/classification
    • Senegal
    • Young Adult


    Dive into the research topics of 'Detecting hybridization in African schistosome species; does egg morphology complement molecular species identification?'. Together they form a unique fingerprint.

    Cite this