Objective: To investigate the genetic diversity and phylogenetic relationship of Sparganum isolates from snakes in Hunan Province.
Methods: The partial mitochondrial NADH dehydrogenase subunit 4 (pnad4) and NADH dehydrogenase subunit 5 (pnad5) genes were amplified using a PCR assay in 7 Sparganum isolates from snakes in Hunan Province and the amplification product was sequenced. The homology and genetic evolution were investigated using the software DNAMAN 7.0, MegAlign, DnaSP 5.0 and MEGA 5.0.
Results: The pnad4 and pnad5 gene sequences were approximately 578 bp and 484 bp in length in the 7 Sparganum isolates from Hunan Province, and the percentages of genetic variations were 0 to 2.8% and 0 to 0.8%, respectively. There were 4 haplotypes detected in both the pnad4 and pnad5 genes, with global haplotype diversities of 0.810 ± 0.016 and 0.905 ± 0.011, nucleotide diversities of 0.006 ± 0.005 and 0.004 ± 0.003, and mean nucleotide variations of 3.960 and 1.905, respectively. Phylogenetic analysis showed that all 7 Sparganum isolates from snakes in Hunan Province were clustered into the same branch with Spirometra erinaceieuropaei isolates from different regions/hosts in the world, which belonged to S. erinaceieuropaei, which were close to Diphyllobothrium latum and far from other tapeworms.
Conclusions: There is a low genetic variation in snake-derived S. erinaceieuropaei isolates from Hunan Province, and both pnad4 and pnad5 genes may be potential molecular genetic markers for identification of S. erinaceieuropaei.
［摘要］ 目的 了解湖南省蛇源裂头蚴种群遗传多样性及其系统发生关系。方法 采用PCR技术扩增湖南省7株蛇源 裂头蚴线粒体 nad4 基因和 nad5 基因部分序列 (pnad4 和 pnad5), 扩增产物测序后用 DNAMAN 7.0、MegAlign、DnaSP 5.0 和 MEGA 5.0 软件进行同源性和系统进化分析。结果 湖南省 7 株蛇源裂头蚴pnad4 和pnad5 基因序列长度分别约为 578 bp 和 484 bp, 其碱基变异率分别为 0~2.8% 和 0~0.8%; 均检测到4个单倍型, 总单倍型多样性分别为 0.810 ± 0.016 和 0.905 ± 0.011, 核苷酸多样性分别为 0.006 ± 0.005 和 0.004 ± 0.003, 平均核苷酸差异为 3.960 和 1.905。构建的系统进化 树显示, 7 株裂头蚴分离株与来自不同地区或不同宿主的猬迭宫绦虫同在一个分支, 属于猬迭宫绦虫; 与阔节迭宫绦虫 相隔较近, 与其他绦虫相隔较远。结论 湖南省蛇源猬迭宫绦虫遗传变异程度低, pnad4 基因和 pnad5 基因均可作为检 测猬迭宫绦虫的分子遗传标记。.
Keywords: Hunan Province; Phylogenetic analysis; Snake-derived Spironmetra erinaceieuropaei; nad4 gene; nad5 gene.