The genetic relationship between Neobenedenia girellae and N. melleni inferred from 28S rRNA sequences
- 海洋环境－已发表论文 
采用一对特定引物对形态相近的单殖吸虫新贝尼登虫和梅氏新贝尼登虫的基因组DNA进行PCR扩增,获得其28SrRNA的350bp左右的特异片段.测序后经软件分析发现两者同源的337bp序列仅存在一个碱基的差异,遗传相似度达99 70%,甚至高于不同海区不同宿主梅氏新贝尼登虫间99 41%的相似度,与贝尼登虫属3个虫种的同源序列间的遗传差异度为2 08%～11 73%.通过UPGMA和MP聚类分析也可看出,新贝尼登虫和梅氏新贝尼登虫的遗传相似性是极为相近的.虽然两种新贝尼登虫的形态特征和遗传多样性极为相似,但它们是否同属于一个种还不能确定,需要经进一步的形态系统比较和更多的基因分析才能得出客观的、公认的结果.The fragments of 350 bp in 28S rRNA from the closely related monogenea of trematoda, Neobenedenia girellae and N. melleni were obtained by polymerase chain reaction (PCR) amplified using a couple of special primers and then sequenced. The results show that the comparison of 28S rRNA sequences, with only a base varies in 337 bp accounting for 0.3% genetic difference, the relative species N. girellae and N. melleni parasitized on the different fishes in different farms display that they possess very high genetic similarity of 99.7%, higher than that of 99.41% for the single species N. melleni cultured in different area, and the intraspecific divergence of N. melleni is 0.59%. Meanwhile, the interspecific differences between the two Neobenedenia and three Benedenia (i.e. B. lutjani, B. rohdei and B. seriolae) range from 2.08% to 11.73%. In addition, UPGMA and MP molecular phylogenetic trees were constructed and proved to be consistent with each other. Though the morphological characteristics and the results of genetic diversity for the two Neobenedenia show the high similarity, whether they belong to a single species or not is still undefined, the more genes of them should be further investigated, combining with the systematicall and detailed morphological study.