Genetic characterisation and phylogenetic status ofwhipworms
(Trichurisspp.)from captive non-human primatesin China,
determined by nuclear and mitochondrial sequencing
Yue Xie, Bo Zhao, Eric P. Hoberg, Mei Li, Xuan Zhou, Xiaobin Gu, Weimin Lai,
Xuerong Peng and Guangyou Yang
Abstract
Background:Whipworms (Nematoda: Trichuridae), among the most common soil-transmitted helminths (STHs), can cause the socioeconomically important disease trichuriasis in various mammalian hosts including humans and non-human primates. For many years,Trichurisfrom non-human primates has been assigned to the same species as the one infecting humansTrichuristrichiura. More recently, several molecular reports challenged this assumption following recognition of aTrichurisspecies complex observed in humans and non-human primates. A refined concept for species limits withinTrichuriscontributes to an understanding of diversity and the potential (zoonotic) transmission among humans and non human primates. In this study, we expanded previous investigations by exploring the diversity ofTrichurisamong eight primates including three Asian autochthonous species (i.e. Rhinopithecus roxellana,Rhinopithecus bietiandNomascus leucogenys). Species-level identification, whether novel or assignable to known lineages ofTrichuris, was based on analyses of nuclear internal transcribed spacers (ITS) and mitochondrial cytochromecoxidase subunit 1 (cox1) genes.
Results:In total, seven genetically distinct subgroups of whipworms were determined to be present among the primates sampled. MostTrichurislineages, including Subgroups 1, 1’, 3, 5 and 6, showed a broad host range and were not restricted to particular primate species; in addition toT. trichiura, a complex ofTrichurisspecies was shown infecting primates. Furthermore, it was assumed thatTrichurisspp. from eitherN. leucogenysandP. hamadryasorR. roxellanaan R. bieti, respectively, were conspecific. Each pair was indicated to be a discrete lineage ofTrichuris, designated, respectively, as Subgroups 1 or 1’and 2, based on integrated genetic and phylogenetic evidence.
Conclusion:These results emphasise that the taxonomy and genetic variations ofTrichurisare more complicated than previously acknowledged. These cumulative molecular and phylogenetic data provide a better understanding of the taxonomy, genetics and evolutionary biology of the whipworms.
copyright:© The Author(s).
Parasites & Vectors(2018) 11:516. DOI:10.1186/s13071-018-3100-5
Read FullText: https://doi.org/10.1186/s13071-018-3100-5
