凡纳滨对虾6个养殖群体遗传多样性的比较分析

中国多批次引进凡纳滨对虾Litopenaeus vannamei并结合生产开展了相对独立的育苗工作，但对引进群体及引进后留种形成的本地群体的遗传变异水平缺乏了解，不利于种质管理及利用。此研究采用AFLP技术对抽查的6个养殖群体进行分析，发现进口群体具有相对较高的遗传多样性水平；养殖性能较好的东方、海星和旭明群体遗传多样性水平与进口群体相近；而乾塘群体遗传变异水平最高，推测可能是与其种质混杂有关；广益群体遗传多样性水平最低，可能已出现近交衰退。通过对各个群体间的遗传距离进行分析，为下一步根据亲缘关系的远近开展群体问杂交育种提供技术依据。     

锦鲤保护性组织RNA提取及引物扩增研究

从养殖锦鲤各种组织中提取完整的RNA, 是分子生物学研究锦鲤应激表达、体色变异、生长发育等功能基因表达的关键实验。在不伤害养殖锦鲤个体健康的情况下, 取用鱼体的鳍条、鳞片、鳃丝、血液4种保护性组织,可以最大程度地减少对珍贵锦鲤个体的损伤, 并达到研究相关基因表达的目的。本研究利用TR izo l法提取RNA, 获得的各样品RNA条带完整、纯度高。结果表明, 4 种保护性组织提取的RNA 经过逆转录反应, 得到了高质量的CDNA。内标基因( B- actin)、热激蛋白基因( hsp70)、金属硫蛋白基因(MT)扩增得到清晰的条带, 通过NCB I数据上的BLAST比对证明, 各序列的同源性在95%以上。利用本研究的方法, 可以充分保护养殖锦鲤个体的完好性, 用于进一步的分子生物学研究。     

Molecular typing of Streptococcus agalactiae isolates from fish

The genetic variability among Streptococcus agalactiae isolates recovered from fish was characterized using single-stranded conformation polymorphism (SSCP) analysis of the intergenic spacer region (ISR), and amplified fragment length polymorphism (AFLP) fingerprinting. A total of 46 S. agalactiae cultures isolated from different fish species and geographic origins as well as related reference strains were included in the study. ISR-SSCP divided the S. agalactiae isolates analysed into five distinct genotypes. Genotype 1 grouped all Kuwait isolates while genotype 4 clustered the majority of non-Kuwait isolates (USA, Brazil and Honduras). AFLP analysis offered a higher resolution level by dividing the isolates into 13 different genotypes. Two different AFLP profiles were identified within the Kuwait isolates. When data from both ISR-SSCP and AFLP were combined through a multidimensional analysis (MDS), a good correlation between geographical origin and genotypes was observed. Both AFLP and ISR-SSCP revealed genetic differences between S. agalactiae isolates from fish. While AFLP offered a higher resolution, ISR-SSCP also provided valid information being a simpler and faster method.     

利用SRAP分子标记技术鉴定大白菜种子纯度

以大白菜品种多抗3及其父母本为研究材料，利用SRAP（相关序列扩增多态性）分子标记方法，通过对54对SRAP标准引物的筛选，获得了能区分大白菜多抗3及其亲本的引物Me4F/Em3R。采Me4F/Em3R引物对对5份多抗3系列商品种子纯度进行检验，种子的纯度分别为75.5%、72%、80.5%、68%和73%，与田间种植纯度鉴定结果符合率分别为94.6%、89.3%、93.2%、95.5%和91.25%。说明利用SRAP分子标记方法对多抗3大白菜一代杂种进行快速、准确的纯度鉴定是可行的。     

三疣梭子蟹野生群体同工酶遗传多态性分析

三疣梭子蟹野生群体同工酶的遗传多态性分析=Isozyme polymorphism in Portunus trituberculatus from wild population ［刊，中］/高保全（中国海洋大学生命科学与技术学部，青岛266003）,刘萍,李健,戴芳钰//水产学报，—2007，31(1).-1～6 采用聚丙烯酰胺不连续凝胶垂直电泳技术对三疣梭子蟹野生群体的同工酶进行检测。分析了48个样本的11种同工酶在三疣梭子蟹肌肉中的表达情况。11种同工酶(MDH、LDH、ME、SOD、 EST、SDH、IDH、ADH、POD、CAT、AAT)共检测出20个基因座位，其中Me-2、Sod-3、Cat-3、Ldh-2共4个座位呈多态(P0.99)，多态座位百分数P为20%。平均每个座位的有效等位基因数目Ae为1.230，预期杂合度He为0.094，实际杂合度Ho为0.175。同时还分析了三疣梭子蟹4个多态座位的Hardy-Weinberg遗传偏离指数d。与日本绒螯蟹、中华绒螯蟹等相比，三疣梭子蟹野生群体的遗传多样性水平较高，种质资源还处于较好的状态。图1表3参22 关键词：三疣梭子蟹；野生群体；同工酶；多态性 E-mail：liuping@ysfri.ac.cn     

瓶鼻海豚和糙齿海豚血清转铁蛋白的初步研究

血清转铁蛋白(serum transferrin,Tf)是一种非血红素结合铁的β球蛋白[1],其主要功能是负责机体中的Fe3 在吸收、储存和利用部位间的传递[2],供合成红细胞的主要成分—血红蛋白(结合和输送氧气的蛋白)和维持核糖核苷酸还原酶(ribonudeotide reductase)的活性[3]。同时,Tf是脊椎     

Using phenotypic variation to determine conservation value: application of a novel approach to Arctic charr

Abstract –  There is a very high degree of discrete variation in phenotype between populations of Arctic charr. This takes the form of variation not only in morphometric and meristic characters traditionally used to distinguish species, but also in characteristics of life-history, behaviour, coloration and ecology. This variability has a number of consequences, one of these is that there is a strong case for the conservation of populations with extreme phenotypes. However, if variation is discrete between populations but continuous across many populations, this poses difficulties in separating those populations of high conservation value from those of lower conservation value. In this paper we describe a statistical technique which enables populations on the extreme edges of the range of phenotypic variation to be identified and apply this to the morphometric characters of charr from 25 populations from across Scotland and Ireland. The technique enables the identification of any proportion of the most extreme phenotypes. When applied to our data, one population (Loch More) was in the top 2 percentile of the most extreme phenotypes from across the range of all populations included. Three populations were within the top 10% most extreme phenotypes (Lochs More, Uaine and Earn) and a further five within the top 20% (previously mentioned lochs plus Lochs Eck, Merkland, Uaine, Talla and Lough Nalughraman). This technique can potentially be used on any species and on any suite of characteristics as an objective measure of conservation value of a population within a continuous phenotypic range.     

大豆品种间DNA限制性片段长度多态性（RFLP）的分析

用６２个大豆ＤＮＡ分子探针与５种限制性内切酶组合，对大豆基因组ＤＮＡ限制性片段长度多态性（ＲＦＬＰ）进行分析，结果表明，所选用的两对材料，其多态性ＲＦＬＰ标记的频率均高达６０％，可作为ＲＦＬＰ作图较理想的亲本，ＲＦＬＰ标记的多态性类型表现为共显性，少数为显性，其中一些标记揭示了２个或２个以上的独立分离的基因座位，不同限制性内切酶的揭示多态性的能力上差异不显著，在杂交片段长度上差异显著并都大于预期，     

云南撒坝猪H-FABP基因多态性及与部分生产性能的关系

采用PCR-RFLP技术检测H-FABP基因5′上游区1125~1817区段HinfⅠ酶切位点在撒坝猪群体中的多态性分布,并采用最小二乘分析模型初步统计分析检测位点多态性与部分生产性能的相关性。结果表明,H-FABP基因等位基因H及基因型Hh在群体中占优势,频率分别为0.6022和0.4194;H-FABP基因在群体中处于Hardy-Weinberg平衡状态;H-FABP基因检测位点基因型间在生长和繁殖性状上不存在不利影响。     

Intron Polymorphisms： Species-specific and Interspecies-comparable Markers

As a component of genes, introns are much more variable than exons. Therefore, introns are an important source of genetic polymorphisms and can be used as genetic markers. By desingning PCR primers in the two exons flanking an intron, the intron can be specifically amplified. There are mainly two types of intron polymorphisms： intron length polymorphism （ILP, due to InDel or SSR） and SNP. ILP can be conveniently detected by electrophoresis, while SNP can be detected by sequencing, ECOTILLING or other methods.