Eamsobhana Praphathip, Song Sze-Looi, Yong Hoi-Sen, Prasartvit Anchana, Boonyong Sudarat, Tungtrongchitr Anchalee
Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University - Bangkok 10700, Thailand.
Institute of Ocean and Earth Sciences, University of Malaya - 50603, Kuala Lumpur, Malaysia.
Acta Trop. 2017 Jul;171:141-145. doi: 10.1016/j.actatropica.2017.03.020. Epub 2017 Mar 27.
The rat lungworm Angiostrongylus cantonensis is a food-borne zoonotic parasite of public health importance worldwide. It is the primary etiologic agent of eosinophilic meningitis and eosinophilic meningoencephalitis in humans in many countries. It is highly endemic in Thailand especially in the northeast region. In this study, A. cantonensis adult worms recovered from the lungs of wild rats in different geographical regions/provinces in Thailand were used to determine their haplotype by means of the mitochondrial partial cytochrome c oxidase subunit I (COI) gene sequence. The results revealed three additional COI haplotypes of A. cantonensis. The geographical isolates of A. cantonensis from Thailand and other countries formed a monophyletic clade distinct from the closely related A. malaysiensis. In the present study, distinct haplotypes were identified in seven regions of Thailand - AC10 in Phitsanulok (northern region), AC11 in Nakhon Phanom (northeastern region), AC15 in Trat (eastern region), AC16 in Chantaburi (eastern region), AC4 in Samut Prakan (central region), AC14 in Kanchanaburi (western region), and AC13 in Ranong (southern region). Phylogenetic analysis revealed that these haplotypes formed distinct lineages. In general, the COI sequences did not differentiate the worldwide geographical isolates of A. cantonensis. This study has further confirmed the presence of COI haplotype diversity in various geographical isolates of A. cantonensis. The COI gene sequence will be a suitable marker for studying population structure, phylogeography and genetic diversity of the rat lungworm.
大鼠肺线虫广州管圆线虫是一种食源性人畜共患寄生虫，在全球范围内具有重要的公共卫生意义。它是许多国家人类嗜酸性粒细胞性脑膜炎和嗜酸性粒细胞性脑膜脑炎的主要病原体。在泰国尤其是东北部地区高度流行。在本研究中，从泰国不同地理区域/省份的野生大鼠肺中回收的广州管圆线虫成虫，通过线粒体细胞色素c氧化酶亚基I（COI）基因部分序列来确定其单倍型。结果揭示了广州管圆线虫另外三种COI单倍型。来自泰国和其他国家的广州管圆线虫地理分离株形成了一个单系分支，与密切相关的马来西亚管圆线虫不同。在本研究中，在泰国的七个地区鉴定出了不同的单倍型——彭世洛（北部地区）的AC10、那空拍侬（东北部地区）的AC11、达叻（东部地区）的AC15、尖竹汶（东部地区）的AC16、北榄（中部地区）的AC4、北碧（西部地区）的AC14和拉廊（南部地区）的AC13。系统发育分析表明，这些单倍型形成了不同的谱系。总体而言，COI序列并未区分广州管圆线虫的全球地理分离株。本研究进一步证实了广州管圆线虫不同地理分离株中存在COI单倍型多样性。COI基因序列将是研究大鼠肺线虫种群结构、系统地理学和遗传多样性的合适标记。
