我国蛋用型地方鸡品种遗传多样性分析

Genetic diversity of egg-type native chicken breeds

对仙居鸡和白耳黄鸡2个蛋用型地方品种mtDNA D-loop区全序列进行PCR扩增和测序,分析其线粒体D-loop区多态性,并结合GenBank中洛岛红和白来航的D-loop区序列进行进化分析。结果表明：2个蛋用型地方品种mtDNA D-loop区全长1 231-1 232bp,共发现18处单核苷酸变异位点和8种单倍型,核苷酸多样性为0.006 51±0.001 09,单倍型多态性为0.781±0.011。系统发育分析发现,2个蛋用型地方品种主要分布在A、B和C 3个进化分支,B和C为优势分支,而2个标准品种则分布在A和E 2个进化分支,E为优势分支。结果提示2个蛋用型地方品种遗传多态性呈中等,与标准品种亲缘关系较远,母系来源也有所不同。这为2个品种的选育利用和有效保种提供遗传背景资料和理论依据。

Baier Yellow chicken and Xianju chicken are excellent indigenous egg-type chicken resources. The complete sequence of control region（D-loop） of mitochondrial DNA of two egg-type chicken breeds was PCR amplified, subse- quently sequenced and compared with the DNA data of standard breeds of Laying Hens annotated in the GenBank. The results indicated that D-loop regions of the two egg-type chicken breeds were 1 231-1 232 bp. Eighteen polymorphic sites were identified across the complete mtDNA D-loop region sequence. Haplotype diversity and nucleotide diversity were 0. 781±0. 011 and 0. 006 51±0. 001 09, respectively. Phylogenetic analysis showed that two egg-type chicken breeds were clustered into three clades A, B and C, B and C were dominated clades. Standard breeds of Laying Hens belonged to two clades A and E, respectively, and E was dominated. It is concluded that the two breeds studied were moderate poly- morphisms at mitochondrial levels, maternal origins were different from standard breeds of Laying Hens. The results of the current study can be used as baseline genetic information for genetic conservation program and breeding.