Melanocortin-1 receptor (MC1R) plays a major role in pigmentation in many species.To investigate if the MC1R gene is associated with coat color in water buffalo,the coding region of MC1R gene of 216 buffalo samples was sequenced,which included 49 black river buffalo (Murrah and Nili-Ravi),136 swamp buffalo (Dehong,Diandongnan,Dechang,Guizhou,and Xilin) with white and gray body,and 31 hybrid offspring of river buffalo Nili-Ravi (or Murrah) and swamp buffalo.Among the three variation sites found,SNP684 was synonymous,while SNP310 and SNP384 were nonsynonymous,leading to p.S104G and p.I128M changes,respectively.Only Individuals carrying homozygote EBR/EBR were black.The genotype and phenotype analysis of the hybrid offspring of black river buffalo and gray swamp buffalo further revealed that the river buffalo type allele EBR or the allele carrying the amino acid p.104S was important for the full function of MC1R.The in silico functional analysis showed that the amino acid substitutions p.G104S and p.M128I had significant impact on the function of MC1R.Above results indicate that the allele EBR or the allele carrying the amino acid p.104S was associated with the black coat color in buffalo.
MIAO YongWang1,2,WU GuiSheng3,WANG Lei2,LI DaLin4,TANG ShouKun5,LIANG JianPing2,MAO HuaMing2,LUO HuaiRong3 & ZHANG YaPing1,6 1 Laboratory for Conservation and Utilization of Bio-resource,Yunnan University,Kunming 650091,China
Extant genes can be modified, or 'tinkered with', to provide new roles or new characteristics of these genes. At the genetic level, this often involves gene duplication and specialization of the resulting genes into particular functions. We investigate how ligand-receptor partnerships evolve after gene duplication. While significant work has been conducted in this area, the examination of additional models should help us better understand the proposed models and potentially reveal novel evolutionary patterns and dynamics. We use bioinformatics, comparative genomics and phylogenetic analyses to show that preproghrelin and prepromotilin descended from a common ancestor and that a gene duplication generated these two genes shortly after the divergence of amphibians and amniotes. The evolutionary history of the receptor family differs from that of their cognate ligands. GPR39 diverges first, and an ancestral receptor gives rise to receptors classified as fish-specific clade A, GHSR and MLNR by successive gene duplications occurring before the divergence of tetrapods and ray-finned fish. The ghrelin/GHSR system is maintained and functionally conserved from fish to mammals. Motilin-MLNR specificity must have arisen by ligand-receptor coevolution after the MLN hormone gene diverged from the GHRL gene in the amniote lineage. Conserved molecular machinery can give rise to new neuroendocrine response mechanisms by the co-option of duplicated genes. Gene duplication is both parsimonious and creative in producing elements for evolutionary tinkering and plays a major role in gene co-option, thus aiding the evolution of greater biological complexity.
Mitochondrial disease currently received an increasing concern. However, the case-control design commonly adopted in this field is vulnerable to genetic background, population stratification and poor data quality. Although the phylogenetic analysis could help solve part of these problems, it has not received adequate attention. This paper is a review of this method as well as its application in mito- chondrial disease study.
WANG ChengYe1,2,3, KONG QingPeng1,2 & ZHANG YaPing1,2? 1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
In view of the geographically closest location to Andaman archipelago, Myanmar was suggested to be the origin place of aboriginal Andamanese. However, for lacking any genetic information from this region, which has prevented to resolve the dispute on whether the aboriginal Andamanese were originated from mainland India or Myanmar. To solve this question and better understand the origin of the aboriginal Andamanese, we screened for haplogroups M31 （from which Andaman-specific lineage M31al branched off） and M32 among 846 mitochondrial DNAs （mtDNAs） sampled across Myanmar. As a result, two Myanmar individuals belonging to haplogroup M31 were identified, and completely sequencing the entire mtDNA genomes of both samples testified that the two M31 individuals observed in Myanmar were probably attributed to the recent gene flow from northeast India populations. Since no root lineages of haplogroup M31 or M32 were observed in Myanmar, it is unlikely that Myanmar may serve as the source place of the aboriginal Andamanese. To get further insight into the origin of this unique population, the detailed phylogenetic and phylogeographic analyses were performed by including additional 7 new entire mtDNA genomes and 113 M31 mtDNAs pinpointed from South Asian populations, and the results suggested that Andaman-specific M31al could in fact trace its origin to northeast India. Time estimation results further indicated that the Andaman archipelago was likely settled by modem humans from northeast India via the land-bridge which connected the Andaman archipelago and Myanmar around the Last Glacial Maximum （LGM）, a scenario in well agreement with the evidence from linguistic and palaeoclimate studies.
To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus and one conservation herd from Yunnan,China.Twenty haplotypes with sixteen polymorphic sites were identified.The number of haplotypes in the nucleus herd of Saba pig and the conservation herd of Banna miniature pig were restricted to three and one,respectively,while the randomly bred pig populations exhibited over six haplotypes.Notably,haplotype diversity in randomly bred populations was significantly greater than the selectively bred populations（h=0.732 vs.0.425 and 0,exact test,P≤0.0036）.These findings demonstrate that selective breeding generated low genetic diversity compared to randomly bred pig breeds.A timely intervention and well programmed breeding approach would stop further genetic diversity reduction in the nucleus and conservation herds of native pig breeds.Otherwise,selective breeding would dramatically reduce genetic diversity in only several years,indicating that sharp contradictions exist between breeding,conservation and genetic diversity.Genetic relationships are discussed based on net genetic distances among pig populations.
