基于线粒体Cytb基因和D-loop区的鸭绿江流域细鳞鱼群体遗传多样性  

Genetic Diversity of Brachymystax lenok Based on Mitochondrial Cytb Gene and D-loop Region from Yalu River Basin

作　　者：王丹丹[1] 宋洁[1] 王旭[1] 乐海梅 WANG Dandan;SONG Jie;WANG Xu;LE Haimei(Institute of Yalu River Basin Studies of Liaodong University,Dandong Liaoning 118003,China)

机构地区：[1]辽东学院鸭绿江流域研究院,辽宁丹东118000

出　　处：《西北农业学报》2023年第11期1675-1685,共11页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：国家自然科学基金(32272757);辽宁省自然科学基金(2022-NLTS-15-04);辽东学院鸭绿江流域研究院开放课题(YLJ20220104)。

摘　　要：旨在研究鸭绿江流域(丹东段)细鳞鱼野生群体与养殖群体的遗传多样性,并探究其种质资源情况。基于细鳞鱼线粒体DNA Cytb基因和D-loop区序列,对宽甸(KD)和丹东江域(DD)2个野生细鳞鱼群体和1个养殖群体的遗传结构与遗传多样性等进行比较研究。结果表明:Cytb基因1141 bp,A+T含量53.55%,G+C含量46.45%,D-loop区序列988 bp,A+T含量62.75%,G+C含量37.25%;基于Cytb和D-loop序列在90个样本中分别检测到42和56个多态性位点,定义了21和26种单倍型,其中KD、DD和YZ群体Cytb基因的单倍型数分别为14、10和7,KD、DD和YZ群体D-loop区单倍型数分别为16、15和10;遗传多样性分析Cytb基因表现出高单倍型多样性(0.986)和低核苷酸多样性(0.00466),而D-loop区表现出高单倍型多样性(0.981)和高水平的核苷酸多样性(0.01982),基于Cytb基因和D-loop区序列KD和DD群体分别具有4个和2个相同单倍型,说明2个细鳞鱼野生群体间的分化程度较小,而养殖群体与野生群体间遗传分化为中度;分子方差分析(AMOVA)发现群体内部的遗传变异(Cytb:73.38%;D-loop:85.91%)占比明显高于群体间的遗传变异(Cytb:26.62%;D-loop:14.09%),表明鸭绿江流域(丹东段)细鳞鱼群体遗传变异主要来源于群体内,不同地理群体间的遗传变异不大;群体单倍型系统发育树表明,KD、DD和YZ群体间互有交叉,均未表现出明显的地理聚集,3个群体间尚未出现明显的地理谱系结构,结果与遗传多样性研究一致。Tajima’s D和Fu and Li’s中性检验显著偏离中性,推测细鳞鱼KD和DD群体可能经历过群体扩张事件,随后处于相对平衡稳定状态。To investigate the genetic diversity among both wild and cultured populations of Brachymystax lenok in Yalu River basin(Dandong section)and to explore the germplasm resources of this species.the genetic structure and diversity of two wilds(KD and DD)and one cultured(YZ)population of Brachymystax lenok were comparatively analyzed based on mitochondrial DNA Cytb gene and D-loop control region.The results showed that the sequences of Cytb gene were 1141 bp,with A+T content(53.55%)similar to G+C content(46.45%).In contrast,the D-loop sequences were 988 bp,and A+T content(62.75%)was significantly higher than G+C content(37.25%).Examination of the 90 samples unveiled 42 and 56 polymorphic sites within the Cytb and D-loop sequences,respectively,This analysis defined 21 and 26 distinct haplotypes correspondingly.Specifically,the Cytb gene-based haplotypes were distributed as 14,10,and 7 within the KD,DD,and YZ populations.In terms of the D-loop analysis,the KD,DD,and YZ populations had 16,15,and 10 haplotypes,respectively.As for genetic diversity,the Cytb gene analysis indicated substantial haplotype diversity but limited nucleotide diversity(0.986,0.00466).Conversely,D-loop regions exhibited both extensive haplotype diversity and heightened nucleotide diversity(0.981,0.01982).The KD and DD wild populations shared four and two common haplotypes,respectively,based on both the Cytb gene and the D-loop region,indicating that the differentiation between the two wild populations was small,the genetic differentiation between the cultured and wild populations was moderate.The analysis of molecular variance(AMOVA)found that genetic variation within populations(Cytb:73.38%;D-loop:85.91%)was significantly higher than among populations(Cytb:26.62%;D-loop:14.09%);the analysis of AMOVA showed that the genetic variation was mainly derived from individual variation within the population,genetic variation between different geographic groups was small;the haplotype phylogenetic tree of the Brachymystax lenok populations showed that the K

关 键 词：鸭绿江流域 细鳞鱼 CYTB基因 D-LOOP区 群体遗传多样性 

分 类 号：S917.4[农业科学—水产科学]