两个不同江豚群体ISSR遗传多样性初步分析

采用ISSR分子标记对中国水域隶属于不同江豚（Neophocaena phocaenoides）亚种的两个群体即长江群体和渤海群体的遗传多样性进行分析。用19条ISSR引物及3对引物组合对两个群体共36个样品的基因组DNA进行PCR扩增，共得到115个清晰的扩增位点，其中多态性位点48个，多态位点百分率（PPL）为41．71％。POPGENE分析结果表明：两个江豚群体的总体遗传多样性水平相对较低（He=0．1643；Ho=0．2413）；长江群体的遗传多样性水平（He=0．1530；Ho=0．2223）稍高于渤海群体（He=0．1402；Ho=0．2059）。Nei＇s遗传多样性分析结果表明群体结构水平较低而基因流水平较高（Gst=0．1049；Nm=4．2676），提示在历史上可能发生过较强的基因交流。我们建议在保护上将两个群体划分为不同的管理单元。

PRELIMINARY ANALYSIS ON GENETIC DIVERSITY OF TWO FINLESS PORPOISE (Neophocaena phocaenoides) POPULATIONS WITH ISSR MARKER

ISSR technique was used to assess the genetic diversity of two finless porpoise(Neophocaena phocaenoides) populations in Chinese waters,i.e.,the Yangtze River population and the Bohai Sea population,which belong to two different subspecies.19 primers and 3 primers combinations that generated highly reproducible and stable DNA fragments were used to screen the genomic DNA of 36 individuals from the two populations.Totally,115 discernible DNA fragments were produced,48 of which were polymorphic loci(PPL=41.71%).As analyzed by software POPGENE,the genetic diversity of Neophocaena phocaenoides was relatively low(H_e=0.164 3;H_o = 0.241 3),the level of genetic variation of the Yangtze River population(H_e=0.153 0;H_o = 0.222 3) was a little higher than that of the Bohai Sea population(H_e=0.140 2;H_o=0.205 9).Analysis of Nei's genetic diversity showed that there was a low level of population genetic structure with a considerable frequency of gene flow(G_(st)=0.104 9;N_m = 4.267 6),indicating that a strong gene exchange might have occurred in the history.We Suggested that they should be treated as two different management units.