粤黄鸡分化品系血液蛋白质多态性基因频率的变化

本试验采用醋酸纤维薄膜电泳和聚丙烯酸胺凝胶电泳方法测定了粤黄鸡4个分化品系(群体)以及石歧杂鸡和杏花鸡的血液蛋白质多态性,观察了多态性血液蛋白质基因频率的变化,根据基因频率计算出6个群体相互之间的相似系数和标准遗传距离及各群的平均杂合度,分别以系统聚类分析和主分量分析方法对这种变化进行研究。结果表明,4个粤黄鸡分化品系大多数多态性血液蛋白质基因频率相近,少数出现品系(群体)间差异,而相似系数和遗传距离说明品系(群体)间分化与选育目的相符;系统聚类分析显示4个粤黄鸡分化品系(群体)与石歧杂鸡间关系较为密切;与杏花鸡相对地较为疏远,主分量分析却清楚地表明了粤黄鸡从石岐杂鸡中的分化以及与杏花鸡的区别。这两种分析方法结果相互补充,而两者的不一致有待进一步研究。另外,平均杂合度似乎也表明了品系(群体)选育程度的差异。

CHANGES IN GENE FREQUENCIES OF BLOOD PROTEIN POLYMORPHISMS IN YUEHUANG CHICKEN LINES

In this experiment the blood protein polymorphisms in four lines of Yuehuang chicken and Shiqiza and Xinghua chicken were determined with cellulose acetate membrance electrophoresis and polyacrylamide gel electrophoresis, and changes in polymorphic gene frequencies, on which the similarity coefficients and Nei's standard genetic distances among the above 6 populations and average heterozygosity per population were calculated, were studied. Systematic cluster analysis and principle component analysis were also carried out based on the gene frequencies of polymorphic loci respectively. The results showed that most of gene frequencies in the determined protein loci were nearly the same and some of them were different among the four Yuehuang lines, and that similarity coefficients and genetic distances between 6 populations suggested the differences among the Yuehuang lines were consistent with the target of breeding. Systematic cluster analysis indicated that the four Yuehuang lines had a close relationship with Shiqiza chicken and a relatively remote relationship with Xinahua chicken. In the other hand, principle component analysis showed that Yuehuang chicken had already differentiated from Shiqiza chicken and that there was difference between Yuehuang chicken and Xinghua chicken. The inconsistency of the two analysis methods needed to be studied further. In addition, the average heterozygosity per population probably showed the degree of selection that each line had been subjected to.