文昌鸡线粒体控制区遗传多态性及系统进化分析

通过对文昌鸡线粒体基因纽(mitochondrial genome,mtDNA)D-loop区全序列的测序和比对,并结合GenBank已经测出D-loop区全序列的红色原鸡的序列,探讨了文昌鸡的遗传多样性和母系起源。结果发现,文昌鸡mtDNAD-loop区全长1231~1232bp,核苷酸多样性(Pi)为0.09757,单倍型多样性(Hd)为0.874。在30只个体中,共发现20处单核苷酸多态位点,10种单倍型。系统发育分析发现,10种单倍型可以分为B、C和E 3个分支。B分支与红色原鸡滇南亚种(Gallus gallus spadiceus)聚为一类,推测这两个分支可能起源于云南、缅甸附近地区的红色原鸡滇南亚种。E分支与红色原鸡(Gallusgallus murghi)聚为一类,推测可能起源于红色原鸡的印度亚种分支。C分支与4个原鸡亚种聚为一类,可能有多个母系起源。本研究从分子水平上为文昌鸡的遗传资源保护和开发利用提供了参考。

The genetic diversity and systematic evolution of Wenchang chickens based on the mitochondrial DNA D-loop sequence

This study aimed at investigating the genetic diversity, relationship and origin of Wenchang chickens. The complete sequence of the mtDNA D-loop was PCR amplified and subsequently sequenced. DNA sequences of the mtDNA D-loop of five red jungle fowl subspecies were collected from the GenBank and used as reference sequences. The results showed that the D-loop region of Wenchang chickens was 1231-1232 bp in length. The nucleotide diversity was 0.09757, and the haplotype diversity was 0.874. The 10 haplotypes were observed based on 20 mutant sites and clustered into three clades B, C, and E. The clade B was clustered with Gallus gallus spadiceus, which indicated the clade B might originate from the continental subspecies of Gallus gallus spadiceus. The clade E was clustered with Gallus gallus murghi, which indicated clade E might originate from the continental subspecies of Gallus gallus murghi. The clade C was clustered with four subspecies of red jungle fowls, which may have multiple origins. The results of the current study can be used as baseline genetic information for genetic conservation program, for instance, to control inbreeding and implement further genetic studies in Wenchang chickens.