广西3个猪种线粒体DNA D-loop序列遗传多样性及系统进化研究

The Genetic Diversity and Phylogenetic Relationships among Three Guangxi Pig Breeds Based on Sequences of mtDNA D-loop

本研究旨在了解广西石头猪、德保猪和隆林猪的起源、群体遗传结构和亲缘关系。通过PCR扩增和测序技术获得3个群体61个个体的线粒体D-loop序列,采用DNASP 5.0进行多态性分析,MEGA 6.0计算各品种间的遗传距离及构建系统发育树。结果显示,3个猪种mtDNA D-loop区全长1 124~1 325 bp,石头猪和德保猪的中间重复序列变异仅存在A型,隆林猪存在A型和B型;石头猪mtDNA D-loop区8个多态性位点归纳出10种单倍型,德保猪8个多态性位点归纳出5种单倍型,隆林猪11个多态性位点归纳出9种单倍型;3种猪单倍型多样度分别为0.857、0.81和0.917,核算多样度分别为0.002 29、0.002 9和0.002 83。石头猪和德保猪可能有相同的母源血统,隆林猪可能有2种母系起源;3个品种猪单倍型多样性较为丰富,但核苷酸多样性匮乏,亟需进行科学保护。

This research aims to learn the origin, genetic diversity and phylogenetic relationships among Guangxi Shitou pigs, Debao pigs and Longlin pigs. The complete mitochondrial DNA control region of 61 pig individuals from three domestic breeds was amplified by PCR and sequenced. The sequences were analyzed by DNASP 5.0. The genetic distance was calculated and the phylogenetic tree were constructed by MEGA 6.0. The results showed that the complete sequence of mtDNA D-loop was 1 124-1 325 bp, the variations in the middle of repeated sequence of Shitou breed and Debao breed belonged type A, and Longlin breed belonged type B. Shitou pigs had 8 polymorphism sites which deduced 10 haplotypes, Debao pigs had 8 polymorphism sites which deduced 5 haplotypes, Longtin pigs had 11 polymorphism sites which deduced 9 haplotypes. The haplotype diversity of three pig breeds were 0.857, 0.81 and 0.917, and the nucleotide diversity were 0.002 29, 0.002 9 and 0.002 83 respectively. Shitou pigs and Debao pigs may share the same maternal lineage and there may be two maternal origins for the Longlin pigs; the haplotype diversity are relatively rich, but the nucleotide diversity of 3 species are deficient, so urgent scientific protection is needed.