Mitochondrial DNA D-Loop Genetic Diversity and Origin of Some Chinese Domestic Buffalo Breeds
|School||Northwest University of Science and Technology|
|Course||Animal Genetic Breeding and Reproduction|
|Keywords||Chinese domestic buffalo breeds mtDNA D-loop heredity diversity origin|
The single strand conformation polymorphism combined with DNA sequencing of control region was used to study the genetic polymorphism of 150 mitochondrial DNA in 10 buffalo breeds. The result showed:The 10 buffalo breeds had high variation in the HV1 of D-loop sequence. 6 haplotypes were indicated in D-loop region by SSCP, and so 110 individuals were sequenced. The results showed that 107 polymorphism sites which were about 11.5% of the all detected sites in the 110 sequences, that of 73 sites were parsim-imformative sites and 34 sites were singleton sites. Its haplotypes diversity was 0.8952±0.0240, nucleotide diversity was 0.0200±0.0056, the average number of nucleotide difference was 18.4450. There was significant difference in breeds, in which Jiangsu Haizi water buffalo’s haplotype diversity, nucleotide diverse and the number of average nucleotide differences was highest, Guizhou black water buffalo, the Wenzhou water buffalo and the Jianghan water buffalo was higher, then others were low.43 kinds various varieties unique single time and 7 kinds single time which share for the variety in the 50 kinds of haplotypes.The biggest sharing haplotype H1 contained 33 individuals of 9 variety except the Jiangsu Haizi water buffalo, haplotypes of H26, H41 and H43 contained more than 5 individuals, haplotypes of H2、H6、H22、H24、H27、H34 and H48 contained 2 or more than 2 individuals, others only contained an individual. The haplotype numbers of Chinese water buffalo’s were different in each breed, the smallest number was 5 and the biggest number was 9; The haplotypes diversity and nucleotide diversity respectively were 0.8332-1.0000 and 0.0096-0.0327. Chinese water buffalo’s average haplotypes diversity and the nucleotide diversity distinction were 0.8952±0.0240 and 0.0200±0.0056, indicated that Chinese water buffalo had rich heredity multiplicity.Take India murrah river water buffalo D-loop sequence (the GenBanK number as AF197215) as the outside group and analysing the relation and system evolvement of 50 kinds of mtDNA haplotypes of Chinese water buffalo, as well as constructing the NJ genealogical tree which showed that Chinese water buffalo was morass water buffalo, and contained 2 lineages, lineage A and lineage B. Lineage A contained 78 individuals of 36 haplotypes, separately accounted for 72% and 70.9%. Although lineage B was not widespread than lineage A in the distribution, lineage B was richer than lineage A in haplotypes and nucleotide diversity. Besides Xiajiang water buffalo, other 9 breeds of Chinese water buffalo had both lineage A and lineage B, indicated that the origin of mtDNA does not have the positive connection with geographic distribution of different buffalo.By distributing the nucleotide mismatch of ten breeds, we discovered that there was no colony expand in breeds, maternal origin of lineage A had colony expand and it was no colony expand about lineage B.