Scholarlink

Background <p><i>Bithynia</i> spp., a key intermediate host of <i>Opisthorchis viverrini</i>, is widely distributed in the lower Mekong sub-region, where opisthorchiasis remains a major public health concern. Understanding the genetic diversity and population structure of these snails is crucial for disease control. <i>Bithynia siamensis</i> sensu lato has been classified into three genetic lineages (I–III) based on cytochrome <i>c</i> oxidase subunit 1 (<i>cox1</i>) and 16S ribosomal RNA (16S rRNA) sequence analysis. This study focuses on Champasak Province, Laos, a highly endemic area of opisthorchiasis with limited genetic data on <i>Bithynia</i> spp.</p> Methods <p><i>Bithynia</i> snails were collected from 12 villages in Khong and Mounlapamok districts, Champasak Province, Laos, between February and August 2024. To compare with previous reports, a total of 246 and 139 samples were analyzed using <i>cox1</i> and 16S rRNA markers, respectively. Genetic diversity, genetic differentiation, and genetic structure were assessed based on these markers. Haplotype networks were constructed based on <i>cox1</i> and 16S RNA sequences to elucidate the genetic lineage of these samples.</p> Results <p>In the present study, only <i>Bithynia siamensis goniomphalos</i> was identified, while <i>B. s. siamensis</i> and <i>B. funiculata</i> were not found. Our findings revealed that both <i>cox1</i> and 16S rRNA sequences exhibited high haplotype diversity among populations but relatively low nucleotide diversity. Two lineages of <i>B. s. goniomphalos</i> (lineages II and III) were detected in the studied areas, exhibiting significant genetic structuring among groups of snail populations from different villages in each lineage. Notably, lineage II was identified in Laos for the first time. The distribution of lineage II was observed near the southern border of Laos and Cambodia.</p> Conclusions <p>This study is the first to use DNA analysis to investigate <i>Bithynia</i> spp. in opisthorchiasis-endemic areas of Champasak Province, where <i>B. s. goniomphalos</i> lineages II and III were detected, but lineage I was not found. Our finding suggested that geographic or environmental factors influence the distribution of specific <i>Bithynia</i> lineages in this region. Many <i>O. viverrini</i> endemic areas in Southeast Asia still lack genetic data on <i>Bithynia</i> snails which could provide valuable insights into the transmission dynamics of opisthorchiasis. Therefore, further investigations should be conducted in these areas using <i>cox1</i> and 16S rRNA sequences for comparison with previous studies.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Genetic structure and geographical distribution of Bithynia siamensis sensu lato from Khong and Mounlapamok districts, Champasak Province, Laos

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年4月2日

查看全文
  • Naruemon Bunchom,
  • Weerachai Saijuntha,
  • Virasack Bounavong,
  • Bounmixay Pakouakeu,
  • Parita Hansana,
  • Pheovaly Soundala,
  • Chavanut Jaroenchaiwattanachote,
  • Takeshi Agatsuma,
  • Marcello Otake Sato,
  • Philippe Buchy,
  • Moritoshi Iwagami

摘要

Background

Bithynia spp., a key intermediate host of Opisthorchis viverrini, is widely distributed in the lower Mekong sub-region, where opisthorchiasis remains a major public health concern. Understanding the genetic diversity and population structure of these snails is crucial for disease control. Bithynia siamensis sensu lato has been classified into three genetic lineages (I–III) based on cytochrome c oxidase subunit 1 (cox1) and 16S ribosomal RNA (16S rRNA) sequence analysis. This study focuses on Champasak Province, Laos, a highly endemic area of opisthorchiasis with limited genetic data on Bithynia spp.

Methods

Bithynia snails were collected from 12 villages in Khong and Mounlapamok districts, Champasak Province, Laos, between February and August 2024. To compare with previous reports, a total of 246 and 139 samples were analyzed using cox1 and 16S rRNA markers, respectively. Genetic diversity, genetic differentiation, and genetic structure were assessed based on these markers. Haplotype networks were constructed based on cox1 and 16S RNA sequences to elucidate the genetic lineage of these samples.

Results

In the present study, only Bithynia siamensis goniomphalos was identified, while B. s. siamensis and B. funiculata were not found. Our findings revealed that both cox1 and 16S rRNA sequences exhibited high haplotype diversity among populations but relatively low nucleotide diversity. Two lineages of B. s. goniomphalos (lineages II and III) were detected in the studied areas, exhibiting significant genetic structuring among groups of snail populations from different villages in each lineage. Notably, lineage II was identified in Laos for the first time. The distribution of lineage II was observed near the southern border of Laos and Cambodia.

Conclusions

This study is the first to use DNA analysis to investigate Bithynia spp. in opisthorchiasis-endemic areas of Champasak Province, where B. s. goniomphalos lineages II and III were detected, but lineage I was not found. Our finding suggested that geographic or environmental factors influence the distribution of specific Bithynia lineages in this region. Many O. viverrini endemic areas in Southeast Asia still lack genetic data on Bithynia snails which could provide valuable insights into the transmission dynamics of opisthorchiasis. Therefore, further investigations should be conducted in these areas using cox1 and 16S rRNA sequences for comparison with previous studies.