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中国幅员辽阔,拥有丰富的鸡种遗传资源.由于中国地方鸡种生产性能相对较低,很难与国内外家禽公司育成的商业品种竞争,现存数目较少,有些已经濒临灭绝.为了进一步了解中国地方鸡品种的遗传多样性状况,本研究采集了分布于中国各地的78个地方鸡品种血样,并利用分布于13条染色体上27个微卫星标记进行分析.通过对2740个样本的检测分析发现,在所有27个微卫星座位中,等位基因数从6~51个不等,平均值为18.74.所检测的78个品种的杂合度(H)均在0.5以上,所有品种的平均杂合度值为0.622,多态信息含量(PIC)平均值为0.573.与国外的同类研究相比,这一结果表明中国的地方鸡品种具有更加广泛的遗传多样性.在27个微卫星座位中,总群内亚群的固定系数(FST)从0.065(LEI0166)到0.209(MCW0078)不等,平均值为0.106.在检测的位点中,只有LEI0194位点在所有的群体中均偏离了Hardy-Weinberg平衡(HWE),而其他位点基本上都处于Hardy-Weinberg平衡状态.由于小群体中的基因漂移及非随机交配,一些保种场保存的地方品种(如狼山鸡)的杂合度相对较低,而保种区的品种由于保种群群体较大,杂合度也就相对较高.中国地方鸡品种的高杂合度与其表型多样性是一致的.通过Nei氏遗传距离和邻接法将中国地方鸡种进行聚类,结果表明,中国地方鸡品种可以分为六大类,分类结果与品种的地理分布基本一致.通过分子生物学手段进行中国地方鸡品种的遗传多样性分析,将对中国地方鸡品种的利用和保护提供重要的理论依据.
China is a vast country with a wealth of genetic resources for chickens, and due to the relatively low performance of local chicken breeds in China, it is difficult to compete with the commercial varieties bred by domestic and foreign poultry companies, with a small number of existing stocks and some already extinct. To learn more about China In this study, blood samples from 78 local chicken breeds distributed throughout China were collected and analyzed using 27 microsatellite markers distributed on 13 chromosomes.According to the detection of 2740 samples, , The alleles in all 27 microsatellite loci ranged from 6 to 51, with an average of 18.74. The heterozygosities (H) of 78 cultivars tested were all above 0.5, and the average heterozygosity With a mean of 0.622 and an average PIC of 0.573.Compared with similar studies abroad, this result indicates that the genetic diversity of Chinese local chicken breeds is more extensive.Among the 27 microsatellite loci, total The fixed coefficient (FST) of intrasubgroups ranged from 0.065 (LEI0166) to 0.209 (MCW0078) with an average of 0.106. Of the tested sites, only the LEI0194 site deviated from Hardy-Weinberg in all populations Balance (HW E), whereas other sites are essentially in Hardy-Weinberg equilibrium. Due to gene drift and non-random mating in small groups, the heterozygosity for some local species preserved in conservation farms (eg, Wolf Pheasant) is relatively low, However, the variety of seedling conservation area had a relatively high population heterogeneity due to the large conservation population, and the high heterozygosity of Chinese local chicken breeds was consistent with its phenotypic diversity.By means of Nei’s genetic distance and adjoining method, The results showed that the Chinese local chicken breeds could be divided into six categories and the classification results were basically the same as the geographical distribution of the breeds.Analysis of the genetic diversity of Chinese local breeds by molecular biology means that the genetic diversity of Chinese local breeds The use of varieties and protection provide an important theoretical basis.