绿头鸭线粒体ND2基因全序列测定及其研究

Determination and Analysis of Mitochondrial ND2 Gene Sequence of Anas platyrhynchos

[目的]分析绿头鸭的系统进化关系。[方法]用PCR产物直接测序的方法,测得4只绿头鸭线粒体ND2基因全序列,结合Gen-Bank中已公布河鸭属野鸭ND2基因全序列,基于N-J法和MP法构建河鸭属野鸭系统进化树。[结果]4只绿头鸭ND2基因序列完全一致,其全长为1 041 bp,碱基A、G、T、C含量分别为28.91%、13.35%、20.75%和36.98%,A+T含量约等于C+G;绿头鸭ND2基因序列与斑嘴鸭完全相同,与其他野鸭的同源性较高。系统进化树结果表明,绿头鸭与斑嘴鸭关系密切,两者共享一个单倍型,它们与棕颈鸭、针尾鸭及绿翅鸭同属于进化枝A。[结论]家鸭可能由绿头鸭和斑嘴鸭驯化而来。

[ Objective ] This study was to analyze the phylogenesis of Anas platyrhynchos. [ Method ] Complete sequence of mitochondrial ND2 gene of 4 Anus platyrhynchos was deterulined by direct DNA sequencing based on the PCR products. Combined with ND2 geue sequences of the Anas linnaeus accessed in GenBank, phylogenetic tree was constructed by Neighbor-joining and maximum parsimony methods. [ Result ] The ND2 gene sequences of 4 A nas platyrhynchos were identical（ 1041 bp in length; the nucleotide contents of A, G, T, and C were 28.91% , 13.35%, 20.75% and 36.98% respectively ; A ＋ T content approximated to that of C ＋ G）. Sequences of ND2 gene of mallard were same as spotbill duck, and had high homology with others. The phylogenetic trees indicated mallard and spotbilled duck were close in genetic relationship, both shared a haplotype; then Philippine duck, green-winged teal and northern pintail fell into branch ＂A＂. [ Conclusion] The domestic duck may be domesticated from mallard and spotbilled duck.