Molecular evolution and co-evolution in Taeniid cestode infections in the world

2014 Fiscal Year Final Research Report

• Project/Area Number: 24256002
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Parasitology (including Sanitary zoology)
• Research Institution: Asahikawa Medical College
• Principal Investigator: ITO Akira 旭川医科大学, 医学部, その他 (70054020)
• Co-Investigator(Kenkyū-buntansha): SAKO Yasuhito 旭川医科大学, 医学部, 教授 (40312459) ; NAKAO Minoru 旭川医科大学, 医学部, 准教授 (70155670) ; NAKAYA Kazuhiro 旭川医科大学, 医学部, 准教授 (70109388) ; YANAGIDA Tetsuya 旭川医科大学, 医学部, 助教 (40431837) ; OKAMOTO Munehiro 京都大学, 霊長類研究所, 教授 (70177096) ; OKAMOTO Yoshiharu 鳥取大学, 農学部, 教授 (50194410)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 寄生虫 / 遺伝子進化 / エキノコックス条虫 / 有鉤条虫 / 無鉤条虫 / アジア条虫

Outline of Final Research Achievements

The purpose of this project is better understanding of the evolutional aspect of pathogenic Taeniid cestodes infections in the world. All four genotypes of Echinococcus multilocularis have been exclusively confirmed from Russia. Mitochondrial DNA analysis of E. granulosus s. s. (G1) revealed that polymorphism of the gene was prominent in the specimens from the Middle East countries > China > Peru, and provided a hypothesis “The ancestral E. granulosus s.s. emerged in the Middle East”. Another purpose is better understanding of fertilization mechanisms in cestodes. Comparative studies of mitochondrial DNA (1N) and nuclear DNA (2N) genes using the sister species, Taenia saginata and T. asiatica, and the two (Asian and Afro/American) genotypes of T. solium sampled from areas where these species and two genotypes were sympatrically distributed revealed different types of hybrids. So, it is clear that out-crossing occurs in hermaphroditic cestode infections if two or more worms mature.

Free Research Field

寄生虫学、感染症学、熱帯病学