Galavani Hossein, Gholizadeh Saber, Hazrati Tappeh Khosrow
Department of Parasitology and Mycology, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran.
Social Determinants of Health Research Center, Urmia University of Medical Sciences, Urmia, Iran; Medical Entomology Department, School of Public Health, Urmia University of Medical Sciences, Urmia, Iran.
Iran J Parasitol. 2016 Jan-Mar;11(1):52-64.
Fascioliasis, caused by Fasciola hepatica and F. gigantica, has medical and economic importance in the world. Molecular approaches comparing traditional methods using for identification and characterization of Fasciola spp. are precise and reliable. The aims of current study were molecular characterization of Fasciola spp. in West Azerbaijan Province, Iran and then comparative analysis of them using GenBank sequences.
A total number of 580 isolates were collected from different hosts in five cities of West Azerbaijan Province, in 2014 from 90 slaughtered cattle (n=50) and sheep (n=40). After morphological identification and DNA extraction, designing specific primer were used to amplification of ITS1, 5.8s and ITS2 regions, 50 samples were conducted to sequence, randomly.
Using morphometric characters 99.14% and 0.86% of isolates identified as F. hepatica and F. gigantica, respectively. PCR amplification of 1081 bp fragment and sequencing result showed 100% similarity with F. hepatica in ITS1 (428 bp), 5.8s (158 bp), and ITS2 (366 bp) regions. Sequence comparison among current study sequences and GenBank data showed 98% identity with 11 nucleotide mismatches. However, in phylogenetic tree F. hepatica sequences of West Azerbaijan Province, Iran, were in a close relationship with Iranian, Asian, and African isolates.
Only F. hepatica species is distributed among sheep and cattle in West Azerbaijan Province Iran. However, 5 and 6 bp variation in ITS1 and ITS2 regions, respectively, is not enough to separate of Fasciola spp. Therefore, more studies are essential for designing new molecular markers to correct species identification.
由肝片吸虫和巨片吸虫引起的片形吸虫病在全球具有医学和经济重要性。用于片形吸虫属鉴定和特征描述的分子方法比传统方法更精确、可靠。本研究的目的是对伊朗西阿塞拜疆省的片形吸虫属进行分子特征分析，然后使用GenBank序列对其进行比较分析。
2014年，从西阿塞拜疆省五个城市的不同宿主中总共收集了580个分离株，其中包括90头屠宰牛（n = 50）和羊（n = 40）。经过形态学鉴定和DNA提取后，使用设计的特异性引物扩增ITS1、5.8s和ITS2区域，随机选取50个样本进行测序。
利用形态学特征，分别有99.14%和0.86%的分离株被鉴定为肝片吸虫和巨片吸虫。1081 bp片段的PCR扩增及测序结果显示，其在ITS1（428 bp）、5.8s（158 bp）和ITS2（366 bp）区域与肝片吸虫具有100%的相似性。本研究序列与GenBank数据的序列比较显示，两者有98%的同一性，存在11个核苷酸错配。然而，在系统发育树中，伊朗西阿塞拜疆省的肝片吸虫序列与伊朗、亚洲和非洲的分离株关系密切。
在伊朗西阿塞拜疆省的绵羊和牛中仅分布有肝片吸虫。然而，ITS1和ITS2区域分别有5和6个碱基的变异，不足以区分片形吸虫属。因此，有必要开展更多研究以设计新的分子标记来准确鉴定物种。
