title: Genetics of the pig tapeworm in madagascar reveal a history of human dispersal and colonization.
abstract: An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation.
authors.affiliation: Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yanagida
authors.affiliation: Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Carod
authors.affiliation: Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Sako
authors.affiliation: Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Nakao
authors.affiliation: US Department of Agriculture, Agricultural Research Service, US National Parasite Collection, Animal Parasitic Diseases Laboratory, Beltsville, Maryland, United States of America.
authors.forename: Eric P
authors.initials: EP
authors.lastname: Hoberg
authors.affiliation: Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Ito
mesh_terms: D000349:Africa; D000818:Animals; D001208:Asia; D044466:Asian People; D044383:Black People; D004272:DNA, Mitochondrial / Q000235:genetics*; D030541:Databases, Genetic; D005828:Genetics, Population; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D008270:Madagascar; D058974:Phylogeography; D013552:Swine / Q000235:genetics / Q000469:parasitology; D041201:Taenia solium / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial