夏南牛遗传多样性分析
毕业论文关键词：夏南牛 微卫星DNA 遗传多样性
The Analysis of Genetic Diversity in Xianan Cattle
Abstract Xianan cattle is the first variety cultivated for meat specially in our country. Inorder to better selection and protection of the resources, the genetic persity of 70inpidual from Xianan groups was analyzed using PCR,polyacrylamide gel electrophoresis(PAGE) and silver staining technology withfourteen microsatellite markers, through collecting each point on the number of allelesfrom Xianan, further effective alleles(Ne), polymorphic information content(PIC) andthe optimal parameters of expected heterozygosity(He) was calculated by Popgen32software. The results showed that 9 of 14 microsatellite loci were polymorphic. At thesame time, a total of 47 alleles were identified on the 9 microsatellite loci withpolymorphism. The average number of alleles was 5.22, the effective alleles werebetween 1.229 and 6.584, and the average number of effective alleles was 4.174. Theheterozygosity was from 0.189 to 0.811 and the average was 0.566. The polymorphicinformation content was up to 0.689 on an average. At ILSTS34 loci the polymorphicinformation content was 0.845 and the other expected heterozygosity was 0.811,which were all the maximum. The polymorphic information content of eachmicrosatellite loci was more than 0.5, showing that the 9 microsatellite markers werehighly polymorphic and the 9 microsatellite markers can be used for this topicresearch. The research is intended to provide the reference data for genetic resourcesprotection, utilization and the future promotion of Xianan cattle.
KeyWords: Xianan cattle Microsatellite DNA Genetic persity
目录
摘要I
Abstract-II
目录III
图清单IV
表清单IV
1绪论1
2材料与方法-2
2.1实验材料2
2.2实验试剂3
2.3仪器设备3
2.4实验方法4
3实验结果与分析9
3.1夏南牛基因组DNA的检测9
3.2PCR扩增产物的检测9
3.3微卫星位点电泳图-10
3.4夏南牛9个微卫星位点的多态性分析13
4讨论14
4.1夏南牛群体内的遗传多样性14
4.2前景15
5结论15
参考文献-17
致谢-19
1 绪论夏南牛是选育而成的中国第一个肉用牛新品种， 它选用我国品质优秀的南阳牛作为母本， 以法国夏洛来牛为父本[1]， 经由导入杂交， 将夏洛来牛的 12.5%-25%外血导入到南阳牛中，再经横交固定阶段，选用开放育种的方式繁育而成[2]，其含有37.5%的夏洛来牛血。相比于中国一般地方黄牛，夏南牛既有南阳牛力强持久、体质健壮、遗传机能稳定以及适应力好的特点，又具有夏洛来牛成长快速、耐粗放、产肉率极高、肉质好等优良性状[3]，因此更适合作为肉牛品种进行推广。但是， 由于近年来人们对夏南牛品种的遗传特性认识不够以及对其保护手段的落后， 夏南牛面临着数量持续减少、 优秀基因遗失、 遗传资源逐渐贫乏等种种难题。为更好地保护和利用夏南牛品种资源，不断提高其遗传性能和生产特质，就须做出一套合理可行的培育方案， 而培育方案的拟定需要以可靠的遗传多样性参数为前提。遗传多样性是基因水平的生物多样性，可称为基因多样性，它反映了一个物种 DNA 序列的差异性。遗传多样性有广、狭义之分[4]，广义的遗传多样性是一切生物（包括单细胞生物、多细胞生物及病毒等非细胞结构生物）所包含遗传信息的总和；狭义的遗传多样性是施立名等人[5]研究所下的定义，指种群间和种群内所有遗传变异的总和。而普通所指的遗传多样性就是种内的遗传多样性，物种能够对人类的搅扰作出适当的反应，其关键要素就是种内的遗传多样性。物种遗传多样性的研究有利于理解物种的遗传关系、物种分类等信息[6]，而且动物遗传多样性与人们的生活和生产密切相关， 是人类长期文明发展过程中不断积累下来的财富。因此，研究物种遗传多样性不论是在科学理论还是在生产实践中都具有重大的意义。随着生物学的发展，物种遗传多样性的研究方式不断改进和完善，表现为从宏观向微观的深入。以往是用形态标记（可见标记）、细胞学标记、生化标记研究物种的多样性[7]。