Kinkar Liina, Korhonen Pasi K, Saarma Urmas, Wang Tao, Zhu Xing-Quan, Harliwong Ivon, Yang Bicheng, Fink J Lynn, Wang Daxi, Chang Bill C H, Chelomina Galina N, Koehler Anson V, Young Neil D, Gasser Robin B
Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia.
Department of Zoology, Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia.
Mol Ecol Resour. 2023 May;23(4):833-843. doi: 10.1111/1755-0998.13760. Epub 2023 Feb 13.
Clonorchis sinensis is a carcinogenic liver fluke that causes clonorchiasis-a neglected tropical disease (NTD) affecting ~35 million people worldwide. No vaccine is available, and chemotherapy relies on one anthelmintic, praziquantel. This parasite has a complex life history and is known to infect a range of species of intermediate (freshwater snails and fish) and definitive (piscivorous) hosts. Despite this biological complexity and the impact of this biocarcinogenic pathogen, there has been no previous study of molecular variation in this parasite on a genome-wide scale. Here, we conducted the first extensive nuclear genomic exploration of C. sinensis individuals (n = 152) representing five distinct populations from mainland China, and one from Far East Russia, and revealed marked genetic variation within this species between "northern" and "southern" geographical regions. The discovery of this variation indicates the existence of biologically distinct variants within C. sinensis, which may have distinct epidemiology, pathogenicity and/or chemotherapic responsiveness. The detection of high heterozygosity within C. sinensis specimens suggests that this parasite has developed mechanisms to readily adapt to changing environments and/or host species during its life history/evolution. From an applied perspective, the identification of invariable genes could assist in finding new intervention targets in this parasite, given the major clinical relevance of clonorchiasis. From a technical perspective, the genomic-informatic workflow established herein will be readily applicable to a wide range of other parasites that cause NTDs.
华支睾吸虫是一种致癌性肝吸虫，可导致华支睾吸虫病，这是一种被忽视的热带病，全球约有3500万人受其影响。目前尚无疫苗可用，化疗依赖于一种驱虫药——吡喹酮。这种寄生虫具有复杂的生活史，已知会感染一系列中间宿主（淡水蜗牛和鱼类）和终末宿主（食鱼动物）。尽管这种生物具有复杂性，且这种生物致癌病原体产生了影响，但此前尚未对该寄生虫进行全基因组规模的分子变异研究。在此，我们对代表中国大陆五个不同种群以及一个来自俄罗斯远东地区的152个华支睾吸虫个体进行了首次广泛的核基因组探索，揭示了该物种在“北方”和“南方”地理区域之间存在显著的遗传变异。这种变异的发现表明华支睾吸虫内部存在生物学上不同的变体，这些变体可能具有不同的流行病学、致病性和/或化疗反应性。对华支睾吸虫样本中高杂合性的检测表明，这种寄生虫在其生活史/进化过程中已发展出易于适应不断变化的环境和/或宿主物种的机制。从应用角度来看，鉴于华支睾吸虫病的主要临床相关性，确定不变基因有助于在这种寄生虫中找到新的干预靶点。从技术角度来看，本文建立的基因组信息工作流程将很容易应用于导致被忽视热带病的其他多种寄生虫。
