长脂拟鲿种群Cytb基因序列的变异及遗传多样性

摘要

To supply a scientific basis for the resource protection and utilization of P .adiposalis, according to 30 individuals of the species collected from Wuyang River which is a tributary of the upper Yuanjiang River (located in the Yangtze River system)and 30 ones from the Lijiang River belonging to the Xijiang River (located in the Pearl River system),the sequence variation and genetic diversity of Cyt b gene in P .adiposalis population were studied for the first time.Results:1 096 bp of Cyt b gene sequence in the species was obtained.A total of six and forty variable loci were detected respectively in Wuyang River and Lijiang River.Six and four haplotypes were respectively diagnosed,the haplotype diversity(H d )was 0.639 and 0.251 respectively,the average genetic distance(P )between the haplotypes was respectively 0.002 0 and 0.024 3,and the nucleotide diversity(P i )was 0.000 80 and 0.006 31 respectively.There were four synonymous mutations sites and two non-synonymous mutations sites in the Cyt b gene of the individuals from the Wuyang River,and 37 synonymous mutations sites and three non-synonymous mutations sites in the Cyt b gene of the specimen from the Lijiang River.According to the 60 individuals of P .adiposalis,a total of 10 haplotypes were diagnosed,the haplotype diversity(H d )was 0.727,the average genetic distance (P)between the haplotypes was 0.030 0,and the nucleotide diversity(P i )was 0.026 03.F st value and N m value between the two populations were 0.817 and 0.06 respectively.The population of P .adiposalis from the Wuyang River showed some differentiation from that in the Lijiang River,but both still belonged to the same population.%为给长脂拟鲿（Pseudobagrus adiposalis ）的保护和利用提供科学依据，以采自珠江水系西江支流漓江、长江水系沅江上游支流㵲阳河的长脂拟！各30尾为材料，研究该种鱼类种群细胞色素 b（Cyt b ）基因序列变异及遗传多样性。结果表明：长脂拟鲿Cyt b 基因序列长1096 bp。其中，㵲阳河种群、漓江种群分别有6个和40个变异位点，分属6个和4个单倍型，单倍型多样性指数（H d ）分别为0．639和0．251，单倍型间平均遗传距离（P）分别为0．0020和0．0243，核苷酸多样性（P i ）分别为0．00080和0．00631。㵲阳河种群 Cyt b 基因序列有4个同义突变和2个非同义突变，漓江种群有37个同义突变和3个非同义突变。漓江与㵲阳河种群 Cyt b 基因序列共定义了10种单倍型，H d 为0．727，P 为0．0300，P i 为0．02603。2个种群间的遗传分化指数（Fst ）为0．817，基因交流值（N m ）为0．06。2个种群间出现了一定程度的分化，但未达到种群水平。