Elsie Isiye, Angela Valcarcel Olmeda, Thomas Curran, David O'Neill, Theo de Waal, Gerald Barry, Aidan O'Hanlon, James O'Shaughnessy, Nicole Keohane McCarthy, Akke Vellinga, Audrey Jenkinson, Alan Johnson, Damien Barrett, Sarah Costello, Annetta Zintl, Denise O'Meara
{"title":"Molecular characterisation of common Culicoides biting midges (Diptera: Ceratopogonidae) in Ireland.","authors":"Elsie Isiye, Angela Valcarcel Olmeda, Thomas Curran, David O'Neill, Theo de Waal, Gerald Barry, Aidan O'Hanlon, James O'Shaughnessy, Nicole Keohane McCarthy, Akke Vellinga, Audrey Jenkinson, Alan Johnson, Damien Barrett, Sarah Costello, Annetta Zintl, Denise O'Meara","doi":"10.1186/s13071-025-06754-7","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) act as vectors for several arboviruses, including bluetongue virus (BTV) and Schmallenberg virus (SBV), which affect livestock health and productivity. In Ireland, limited genetic data are available regarding the diversity of Culicoides species. This study represents the first attempt to characterise Culicoides in this region using molecular techniques.</p><p><strong>Methods: </strong>Adult Culicoides samples were captured using Onderstepoort Veterinary Institute (OVI) traps across six locations in Ireland. Subsequent molecular analyses involved polymerase chain reaction (PCR) and sequencing of the cytochrome oxidase subunit 1 (CO1) and the internal transcriber spacer (ITS) barcoding regions to obtain species identities. In addition, using both markers, we inferred the population genetic structure and potential colonisation pathways of Culicoides obsoletus sensu stricto (s. str.), the major vector species in Ireland.</p><p><strong>Results: </strong>DNA barcoding facilitated identification of 177 specimens. Eight common Culicoides species were identified through DNA barcoding of CO1 and ITS gene regions. The presence of putative vectors of bluetongue virus (BTV) and Schmallenberg virus (SBV) were also confirmed, including species in the subgenus Avaritia (C. obsoletus s. str., C. scoticus, C. chiopterus, and C. dewulfi) and subgenus Culicoides s. str. (C. pulicaris and C. punctatus). Phylogenetic analysis confirmed the relationship between these vector species and facilitated the placement of Culicoides spp. that could not be identified to species level through DNA barcoding. Haplotype network analysis of C. obsoletus showed that some haplotypes of these species are shared between Continental Europe, the UK, and Ireland, suggesting a possible incursion pathway for this vector.</p><p><strong>Conclusions: </strong>DNA barcoding employing a combination of two barcodes, CO1 and ITS, proved effective in identifying Culicoides, especially species within the obsoletus complex, which are difficult to morphologically distinguish. Our findings also suggest that investigation of the population genetic structure of Culicoides spp. could be used to model the potential introduction routes of midge-borne pathogens into the country.</p>","PeriodicalId":19793,"journal":{"name":"Parasites & Vectors","volume":"18 1","pages":"149"},"PeriodicalIF":3.0000,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12016113/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Parasites & Vectors","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1186/s13071-025-06754-7","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PARASITOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) act as vectors for several arboviruses, including bluetongue virus (BTV) and Schmallenberg virus (SBV), which affect livestock health and productivity. In Ireland, limited genetic data are available regarding the diversity of Culicoides species. This study represents the first attempt to characterise Culicoides in this region using molecular techniques.
Methods: Adult Culicoides samples were captured using Onderstepoort Veterinary Institute (OVI) traps across six locations in Ireland. Subsequent molecular analyses involved polymerase chain reaction (PCR) and sequencing of the cytochrome oxidase subunit 1 (CO1) and the internal transcriber spacer (ITS) barcoding regions to obtain species identities. In addition, using both markers, we inferred the population genetic structure and potential colonisation pathways of Culicoides obsoletus sensu stricto (s. str.), the major vector species in Ireland.
Results: DNA barcoding facilitated identification of 177 specimens. Eight common Culicoides species were identified through DNA barcoding of CO1 and ITS gene regions. The presence of putative vectors of bluetongue virus (BTV) and Schmallenberg virus (SBV) were also confirmed, including species in the subgenus Avaritia (C. obsoletus s. str., C. scoticus, C. chiopterus, and C. dewulfi) and subgenus Culicoides s. str. (C. pulicaris and C. punctatus). Phylogenetic analysis confirmed the relationship between these vector species and facilitated the placement of Culicoides spp. that could not be identified to species level through DNA barcoding. Haplotype network analysis of C. obsoletus showed that some haplotypes of these species are shared between Continental Europe, the UK, and Ireland, suggesting a possible incursion pathway for this vector.
Conclusions: DNA barcoding employing a combination of two barcodes, CO1 and ITS, proved effective in identifying Culicoides, especially species within the obsoletus complex, which are difficult to morphologically distinguish. Our findings also suggest that investigation of the population genetic structure of Culicoides spp. could be used to model the potential introduction routes of midge-borne pathogens into the country.
背景：库蠓属蠓（双翅目：蠓科）是几种虫媒病毒的媒介，包括蓝舌病病毒（BTV）和施马伦贝格病毒（SBV），影响牲畜健康和生产力。在爱尔兰，关于库蠓物种多样性的遗传数据有限。本研究首次尝试利用分子技术对该地区库蠓类进行表征。方法：在爱尔兰的六个地点使用Onderstepoort兽医研究所（OVI）诱捕器捕获库蠓成虫样本。随后的分子分析包括聚合酶链反应（PCR）和细胞色素氧化酶亚基1 （CO1）和内部转录间隔（ITS）条形码区域的测序，以获得物种身份。此外，利用这两个标记，我们推断了爱尔兰主要病媒种库蠓（Culicoides obsoletus sensu stricto, s. str.）的种群遗传结构和潜在的定殖途径。结果：DNA条形码技术对177份标本进行了鉴定。通过CO1和ITS基因区DNA条形码鉴定了8种库蠓。此外，还发现了蓝舌病病毒（BTV）和施马伦贝格病毒（Schmallenberg virus， SBV）的传播媒介，包括蓝舌病螨亚属（灰舌病螨、褐舌病螨、chiopterus和dewulfi蓝舌病螨）和库蠓亚属（纹舌病螨和斑点病螨）。系统发育分析证实了这些媒介物种之间的关系，并有助于将无法通过DNA条形码识别的库蠓定位到物种水平。对C. obsoletus的单倍型网络分析表明，这些物种的一些单倍型在欧洲大陆、英国和爱尔兰之间是共享的，这表明该媒介可能有入侵途径。结论：采用CO1和ITS两种条形码组合的DNA条形码技术可以有效地识别库蠓，特别是在形态上难以区分的库蠓复合体内。本研究结果还表明，库蠓种群遗传结构的调查可用于模拟媒介传播病原体传入我国的潜在途径。
期刊介绍：
Parasites & Vectors is an open access, peer-reviewed online journal dealing with the biology of parasites, parasitic diseases, intermediate hosts, vectors and vector-borne pathogens. Manuscripts published in this journal will be available to all worldwide, with no barriers to access, immediately following acceptance. However, authors retain the copyright of their material and may use it, or distribute it, as they wish.
Manuscripts on all aspects of the basic and applied biology of parasites, intermediate hosts, vectors and vector-borne pathogens will be considered. In addition to the traditional and well-established areas of science in these fields, we also aim to provide a vehicle for publication of the rapidly developing resources and technology in parasite, intermediate host and vector genomics and their impacts on biological research. We are able to publish large datasets and extensive results, frequently associated with genomic and post-genomic technologies, which are not readily accommodated in traditional journals. Manuscripts addressing broader issues, for example economics, social sciences and global climate change in relation to parasites, vectors and disease control, are also welcomed.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
