Ichikawa-Seki Madoka, Ortiz Pedro, Cabrera Maria, Hobán Cristian, Itagaki Tadashi
Laboratory of Veterinary Parasitology, Faculty of Agriculture, Iwate University, Ueda 3-18-8, Morioka 020-8550, Japan.
Laboratorio de Inmunología, Facultad de Ciencias Veterinarias, Universidad Nacional de Cajamarca, Cajamarca, Peru.
Parasitol Int. 2016 Jun;65(3):171-4. doi: 10.1016/j.parint.2015.11.010. Epub 2015 Nov 30.
The causative agent of fasciolosis in South America is thought to be Fasciola hepatica. In this study, Fasciola flukes from Peru were analyzed to investigate their genetic structure and phylogenetic relationships with those from other countries. Fasciola flukes were collected from the three definitive host species: cattle, sheep, and pigs. They were identified as F. hepatica because mature sperms were observed in their seminal vesicles, and also they displayed Fh type, which has an identical fragment pattern to F. hepatica in the nuclear internal transcribed spacer 1. Eight haplotypes were obtained from the mitochondrial NADH dehydrogenase subunit 1 (nad1) sequences of Peruvian F. hepatica; however, no special difference in genetic structure was observed between the three host species. Its extremely low genetic diversity suggests that the Peruvian population was introduced from other regions. Nad1 haplotypes identical to those of Peruvian F. hepatica were detected in China, Uruguay, Italy, Iran, and Australia. Our results indicate that F. hepatica rapidly expanded its range due to human migration. Future studies are required to elucidate dispersal route of F. hepatica from Europe, its probable origin, to other areas, including Peru.
南美洲肝片吸虫病的病原体被认为是肝片吸虫。在本研究中，对来自秘鲁的肝片吸虫进行了分析，以研究其遗传结构以及与其他国家肝片吸虫的系统发育关系。肝片吸虫从三种终末宿主物种中采集：牛、羊和猪。它们被鉴定为肝片吸虫，因为在其精囊中观察到了成熟精子，并且它们还显示出Fh型，其在核糖体DNA内转录间隔区1中的片段模式与肝片吸虫相同。从秘鲁肝片吸虫的线粒体烟酰胺腺嘌呤二核苷酸脱氢酶亚基1（nad1）序列中获得了8个单倍型；然而，在这三种宿主物种之间未观察到遗传结构上的特殊差异。其极低的遗传多样性表明秘鲁种群是从其他地区引入的。在中国、乌拉圭、意大利、伊朗和澳大利亚检测到了与秘鲁肝片吸虫相同的nad1单倍型。我们的结果表明，由于人类迁移，肝片吸虫迅速扩大了其分布范围。未来需要开展研究以阐明肝片吸虫从其可能的起源地欧洲传播到包括秘鲁在内的其他地区的扩散途径。
