长江江豚微卫星DNA分离的初步研究

为了开发物种特异性微卫星标记,本文采用一种改良的快速微卫星分离法(FIASCO)从长江江豚(Neophocaena phocaenoides asiaeorientalis)的基因组中筛选得到72条微卫星DNA序列。根据重复单元的排列特点,完美型、非完美型及复合型序列所占的比例分别为58.3%、22.2%和19.5%。选择其中30条序列设计PCR扩增引物,并用12个随机选择的长江江豚样品进行多态性筛选。初步结果表明其中14对引物的扩增产物稳定并且具有多态性;在每个座位上获得2-13个等位基因,平均等位基因数为5.87个;14个微卫星座位的平均观察杂合度(Ho)和期望杂合度(He)分别为0.560和0.709。本研究获得了长江江豚的第一批物种特异性微卫星座位及其扩增引物,这些微卫星标记将在后续的保护遗传学研究中发挥重要作用。  

A PILOT STUDY ON ISOLATION OF MICROSATELLITE DNA IN THE YANGTZE FINLESS PORPOISE (NEOPHOCAENA PHOCAENOIDES ASIAEORIENTALIS)

To the aim of developing specific microsatellite markers for the endangered Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis,72 microsatellite DNA sequences were isolated using an improved FIASCO (Fast Isolation by AFLP of Sequences Containing Repeats) protocol.According to Weber's classification rules,these sequences were divided into three categories:perfect repeat sequences (58.3% of total),imperfect repeat sequences (22.2%),and compound repeat sequences (19.5%).Thirty PCR primer pairs were designed and synthesized,and then screened by a sample panel of 12 random selected Yangtze finless porpoises.As a result,14 of them were proved to be polymorphic exhibiting 2 to 13 alleles (mean 5.86 alleles/locus).Their average observed heterozygosity and expected heterozygosity were 0.560 and 0.709 respectively.These are the first batch of specific microsatellite markers for the Yangtze finless porpoise,and they should play great role in succedent conservation genetics studies.