Department of Animal Biodiversity, Higher Institute of Sciences and Technology of Environment, Borj Cedria, Tunisia.
Exp Parasitol. 2013 Nov;135(3):471-8. doi: 10.1016/j.exppara.2013.08.006. Epub 2013 Aug 27.
The aim of the present study is to investigate for the first time the genetic diversity of samples identified morphologically as Fasciola hepatica (Platyhelminthes: Trematoda: Digenea) (n=66) from sheep and cattle from two localities of Sardinia and to compare them with available data from other localities by partial sequences of the first (ITS-1), the 5.8S, and second (ITS-2) Internal Transcribed Spacers (ITS) of nuclear ribosomal DNA (rDNA) genes, the mitochondrial cytochrome c oxidase subunit I (COI), and nicotinamide adenine dinucleotide dehydrogenase subunit I (ND1) genes. Comparison of the sequences from Sardinia with sequences of Fasciola spp. from GenBank confirmed that all samples belong to the species F. hepatica. The nucleotide sequencing of ITS rDNA showed no nucleotide variation in the ITS-1, 5.8S and ITS-2 rDNA sequences among all Sardinian samples, comparing with two ITS-2 haplotypes in standard F. hepatica, showing a substitution C/T in 20 position 859, reported previously from Tunisia, Algeria, Australia, Uruguay and Spain. The present study shows that in Sardinian sheep and cattle there is the most frequent haplotype (FhITS-H1) of F. hepatica species from South Europe. Considering NDI sequences, the phylogenetic trees showed reliable grouping among the haplotypes of F. hepatica from Sardinia and the mitochondrial lineage I, including the main N1 haplotype, observed previously from Europe (Russia, Belarus, Ukraine and Bulgaria), Armenia, West Africa (Nigeria), America (Uruguay and USA), Asia (Turkey, Japan, and China), Georgia, Turkmenistan, Azerbaijan and Australia. Furthermore, common haplotypes FhCOI-H1 and FhCOI-H2 of F. hepatica from Sardinia also corresponded mostly to the first lineage including the main C1 haplotype reported previously from Eastern European and Western Asian populations, they belonged just to a phylogenically distinguishable clade, as F. hepatica from Australia, France, Turkey, Uruguay, Russia, Armenia, Ukraine, Belarus, Turkmenistan, USA, Tunisia and Algeria, indicating that this is the main haplotype involved in the spread of F. hepatica throughout all continents.
本研究旨在首次调查来自撒丁岛两个地区绵羊和牛中形态学上鉴定为 Fasciola hepatica（扁形动物门：吸虫纲：双腔吸虫）（n=66）的样本的遗传多样性，并将其与来自其他地区的可用数据进行比较，使用核核糖体 DNA（rDNA）基因的第一（ITS-1）、5.8S 和第二（ITS-2）内部转录间隔区（ITS）、线粒体细胞色素 c 氧化酶亚单位 I（COI）和烟酰胺腺嘌呤二核苷酸脱氢酶亚单位 I（ND1）基因的部分序列。将来自撒丁岛的序列与 GenBank 中 Fasciola spp. 的序列进行比较，证实所有样本均属于 Fasciola hepatica 种。ITS rDNA 的核苷酸测序显示，所有撒丁岛样本的 ITS-1、5.8S 和 ITS-2 rDNA 序列均无核苷酸变异，与来自突尼斯、阿尔及利亚、澳大利亚、乌拉圭和西班牙的标准 Fasciola hepatica 的两个 ITS-2 单倍型相比，在 20 位 859 处显示 C/T 取代，该取代先前在欧洲（俄罗斯、白俄罗斯、乌克兰和保加利亚）、亚美尼亚、西非（尼日利亚）、美洲（乌拉圭和美国）、亚洲（土耳其、日本和中国）、格鲁吉亚、土库曼斯坦、阿塞拜疆和澳大利亚观察到。考虑到 ND1 序列，系统发育树显示来自撒丁岛的 Fasciola hepatica 单倍型与线粒体谱系 I 之间的可靠分组，包括先前在欧洲（俄罗斯、白俄罗斯、乌克兰和保加利亚）、亚美尼亚、西非（尼日利亚）、美洲（乌拉圭和美国）、亚洲（土耳其、日本和中国）、格鲁吉亚、土库曼斯坦、阿塞拜疆和澳大利亚观察到的主要 N1 单倍型。此外，来自撒丁岛的 Fasciola hepatica 的常见单倍型 FhCOI-H1 和 FhCOI-H2 也主要与包括先前在东欧和西亚人群中报道的主要 C1 单倍型在内的第一个谱系相对应，它们仅属于一个在系统发育上可区分的分支，如来自澳大利亚、法国、土耳其、乌拉圭、俄罗斯、亚美尼亚、乌克兰、白俄罗斯、土库曼斯坦、美国、突尼斯和阿尔及利亚的 Fasciola hepatica，表明这是参与 Fasciola hepatica 在各大洲传播的主要单倍型。
