【作者】 杨燕；

【导师】 张英汉； 马月辉；

【作者基本信息】 西北农林科技大学 ， 动物遗传育种与繁殖， 2004， 硕士

【摘要】 根据项目任务要求，本研究利用微卫星标记技术，对我国的7个地方绵羊品种：湖羊、哈萨克羊、巴音布鲁克羊、阿勒泰羊、黑藏羊、白藏羊和晋中羊的遗传多样性进行研究，探讨了它们之间群体内、群体间的遗传变异。研究结果如下：1.在28个微卫星位点中，共检测到286个等位基因，平均每个位点为10.6个。其中以AGLA269位点检测到的等位基因数目最多，为18个；其次是BM4311位点，为15个等位基因。等位基因数目最少的位点为BM315、ILSTS021位点，分别检测到4个等位基因。2.运用软件对受试羊进行优势等位基因和稀有等位基因分析，结果表明:28个微卫星位点都有优势等位基因存在。有11个位点检测到稀有等位基因。3.以等位基因频率为基础，得出位点的平均杂合度在0.0629～0.5903之间，群体平均杂合度在0.3421～0.4215之间，属于中度杂合群体和中度杂合位点。根据统计结果除BM315、ILSTS021的PIC＜0.5之外，其余26个位点均为高度多态位点。在26个高度多态位点中，0.60＜PIC＜0.70 的共有4个位点，占到15.38%，0.70＜PIC＜0.80的共有13个位点，占到50.00%，0.80＜PIC＜0.90的共有9个，占到34.62％。在26个高度多态位点中，以AGLA269位点的多态信息含量最高，达到0.8712；ILSTS021位点的多态信息含量最小，为0.3453。在7个品种中，湖羊的多态信息含量最高，为0.7590；哈萨克羊的最低，为0.7317。4.对受试羊进行有效等位基因分析表明：在湖羊检测到的有效等位基因数目最多，为5.5309。有19个位点的平均有效等位基因数目都超过4个。 5.运用软件，进行哈代—温伯格平衡检验，我们得出几乎所有的位点在7个绵羊品种中都处于哈代—温伯格不平衡状态，只有个别位点在个别品种中达到平衡，如BMC1206 在晋中羊品种中，ILSTS021在哈萨克羊品种中基本达到平衡。6.中性测试结果表明：共有5个位点（MB009,BM1341,BM3033,BMS6444,BM315）属于中性位点。7.对受试羊进行基因流分析，发现巴音布鲁克羊和阿拉泰羊之间有较大的基因流（7.5731），基因流相对最小的是黑藏羊和湖羊之间，其值为3.0964。8. F-统计量分析表明：各标记FST的变化范围是从BMS875的0.0293到ILSTS021的0.3969，平均值为0.0747；群体每代迁移数在0.3799 (ILSTS021)和8.2854 (BMS875)<WP=7>之间变动，平均值为3.0964。9.运用共祖遗传距离，采用UPGMA法和NJ法对受试羊进行聚类分析可以看到：湖羊与哈萨克羊始终有较近的亲缘关系；巴音布鲁克羊与阿勒泰羊也存在较近的遗传关系。而黑藏羊、白藏羊与晋中羊的聚类情况比较复杂。更多还原

【Abstract】 The genetic diversity of 7 native sheep breeds in China was analyzed with the microsatellite marker technology based on the requirement of project assignment. The sheep breeds were as followings：Hu sheep、Hasake sheep、Bayinbuluke sheep、Aleitai sheep、 Heizang sheep、Baizang sheep and Jin sheep. The thesis discussed the genetic variation within population and among populations. The results were followed: 1. The 286 alleles were tested in 28 microsatellite loci, and each locus had 10.6. The most was 18 in AGLA269, the second was 15 in BM4311. The least was 4 in BM315 and ILSTS021.2. The results showed that 28 loci had the highly dominant alleles and 11 loci had private alleles.3. The mean heterozygosity of different locus varied from 0.0629 to 0.5903, and of different population was from 0.3421 to 0.4215, which belonged to middle heterozygosity locus and population. The PIC value were less than 0.5 in BM315、ILSTS021, the other 26 loci were high diversity. In 26 loci, there were 4 loci which PIC value varied from 0.60 to 0.70, 13 loci which PIC value was from 0.70 to 0.80, and the other 9 loci’s PIC value varied from 0.80 to 0.90. The PIC value in AGLA269 locus was the highest and in ILSTS021 locus was the smallest, which values were 0.8712 and 0.3453 each. The most value was 0.7590 in Hu sheep and the least was 0.7317 in Hasake sheep. 4. The Hu sheep had the most effective number of allele, which was 5.5309. The average effective number of allele in 19 loci was all more than 4.5. Almost all of the loci were not in the HDW equilibrium through the test of HDW with x2 in 7 sheep breeds, except BMC1206 locus in the Jinzhong sheep and ILSTS021 locus in the Hasake sheep.6. The Neutrality Test showed that 5 loci (MB009, BM1341, BM3033, BMS6444, BM315) belonged to neutrality locus.7. There was the major gene flow between Buyinbuluke sheep and Aleitai sheep (the <WP=9>value was 7.5731), and the relative least was between Heizang sheep and Hu sheep (the value was 3.0964).8. The F-statistic analysis indicated that the FST of different locus varied from 0.0293 (in BMS875) to 0.3969 (in ILSTS021), the average was 0.0747. The Nm was from 0.3799 (in ILSTS021) to 8.2854 (in BMS875), and the mean value was 3.0964.9. Adopted the method of UPGMA and NJ with the D coa genetic distance in the 7 sheep breeds, the dendrograms were drawed: Hu sheep and Hasake sheep, Bayinbuluke sheep and Aleitai sheep were in the close relationship each other. The cluster of other three breeds was complex.更多还原