| To study the phylogenetic relationships and evolution of domestic geese in China, using the sequences of partial mitochondrial control region ( CR )(approximately 1042bp in length) and the complete sequence (1143bp) of cytochrome b ( Cyt b ) were determined from 17 breeds representing 2 species, Anser cygnoides (14 breeds in China) and Anser anser (2 breeds (Rhin & Landoise) in Europe and Yili breed in China). To confirm the results based on CR and Cyt b. Analyzing these data together with the same sequence part available in GenBank, we can draw some conclusions as follow:There are 94 variable positions define 20 hapotypes in CR of 100 domestic geese, H6 is major haplotype among 14 breeds (Anser cygnoides), and no shared haplotype between Anser anser and Anser cygnoides. Supporting the hypothesis of dual origin of domestic geese (the same results based on Cyt b). Domestic geese in China was descent from Anser cygnoides except for the Yili breed that derived from Anser anser. Neither the western subspecies Anser anser anser nor me eastern Anser anser rubrirostris are the ancestor of domestic geese (Anser cygnoides) in China.The average nucleotide diversity in Anser anser (1.179) was higher than in Anser cygnoides (0.088) and varied different domestic breeds (0~ 0.135). The nucleotide diversity was 0.211-0.272 between Huoyan breed and other Chinese breeds of Anser cygnoides, higher than between each other Chinese swan geese breeds 0-0.094(exception for Huoyan breed). Low Nucleotide diversity indicated that genetic differentiation coming from the same origin was relatively low, and may be have a recent common ancestry for the populations. We can conjecture that the Anser cygnoides were domesticated in the multiple places including Shantou in Guangdong (ShitOU breed), Sichuan (Sichuan white breed), Jiangsu (Taihu breed), Hunan (Xupu breed), Anhui (Van breed) and Laiyang in Shandong (Huoyan breed).During the formation of domestic breeds from Anser cygnoides, there are relatively relationship between the genetic differentiation of domestic geese and some geographic scale.The genetic differentiation is relatively high between Huoyan and other breeds of Anser cygnoides, whereas between in each other breeds of Anser cygnoides are clearly low genetic differentitation(exception for Huoyan breed). The genetic variation is high among graylag geese breeds (Anser anser).The conserved structured features are clearly evident by alignment between Anser anser and Anser cygnoides.P-(from 265 to 293 positions), D-(from 371 to 395 positions), and C-boxes(from 419 to 445 positions) are located in the central domain, and CSB-l(from 719 to 745 positions) is located in domain III for domestic geese CR partial sequences (1042bp). Most of the nucleotide differences between the species are concentrated to the 5' and 3' hypervariable domains I and III of the control region. Although only 246bp sequenced in domain I, transition (S),transversion(V) and percentage of divergence (P) are higher than domain III. The average sequence divergences between Anser anser and Anser cygnoides in this study in domain I,domain II and domain III are 9.86%, 1.36% and X49%,respectively.The number of transition is higher than that of transversion in domestic geese CR.The phylogenetic analysis was based on 1042bp nucleotide positions of the mitochondria control region by maximum parsimony, maximum likehood, and minimum evolution and obtained 3 trees with nearly identical topology.The species grouped into two mtDNA lineages (MP,ML,ME 100%): (1) Cygnus atratusjiranta, Chloephaga picta, Alopochen aegyptiacus, Cereopsis novaehollandiae and Coscoroba coscoroba, (2) Anser. Phylogenetic anayses of the concatenated sequences split Anser into four clades including: (1) Anser rossii, Anser caerulescens, Anser canagica and Anser indicus, (2) Anser erythropus, Anser fabalis rossicus, Anser albifrons and Anser brachyrhynckus,(3) Anser cygnoldes(14 breeds) , (4) Anser anser anser, Anser anser rvbrirostris,Anser anrer(Landoise,Rhin,Yili breed).From phyletic trees...
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