The worldwide chicken gene pool encompasses a remarkable,but shrinking,number of divergently selected breeds of diverse origin.This study was a large-scale genome-wide analysis of the landscape of the complex molecula...The worldwide chicken gene pool encompasses a remarkable,but shrinking,number of divergently selected breeds of diverse origin.This study was a large-scale genome-wide analysis of the landscape of the complex molecular architecture,genetic variability,and detailed structure among 49 populations.These populations represent a significant sample of the world's chicken breeds from Europe(Russia,Czech Republic,France,Spain,UK,etc.),Asia(China),North America(USA),and Oceania(Australia).Based on the results of breed genotyping using the Illumina 60K single nucleotide polymorphism(SNP)chip,a bioinformatic analysis was carried out.This included the calculation of heterozygosity/homozygosity statistics,inbreeding coefficients,and effective population size.It also included assessment of linkage disequilibrium and construction of phylogenetic trees.Using multidimensional scaling,principal component analysis,and ADMIXTURE-assisted global ancestry analysis,we explored the genetic structure of populations and subpopulations in each breed.An overall 49-population phylogeny analysis was also performed,and a refined evolutionary model of chicken breed formation was proposed,which included egg,meat,dual-purpose types,and ambiguous breeds.Such a large-scale survey of genetic resources in poultry farming using modern genomic methods is of great interest both from the viewpoint of a general understanding of the genetics of the domestic chicken and for the further development of genomic technologies and approaches in poultry breeding.In general,whole genome SNP genotyping of promising chicken breeds from the worldwide gene pool will promote the further development of modern genomic science as applied to poultry.展开更多
supported by the China Animal Disease Prevention and Control Center;the China Agriculture Research System Poultry-Related Science and Technology Innovation Team of Peking, China （CARS-PSTP）
Flow cytometry(FCM) technique has been widely applied to estimating the genome size of various higher plants. However, there is few report about its application in algae. In this study, an optimized procedure of FCM w...Flow cytometry(FCM) technique has been widely applied to estimating the genome size of various higher plants. However, there is few report about its application in algae. In this study, an optimized procedure of FCM was exploited to estimate the genome size of two eukaryotic algae. For analyzing Alexandrium catenella, an important red tide species, the whole cell instead of isolated nucleus was studied, and chicken erythrocytes were used as an internal reference. The genome size of A. catenella was estimated to be 56.48 ± 4.14 Gb(1C), approximately nineteen times larger than that of human genome. For analyzing Gracilariopsis lemaneiformis, an important economical red alga, the purified nucleus was employed, and Arabidopsis thaliana and Chondrus crispus were used as internal references, respectively. The genome size of Gp. lemaneiformis was 97.35 ± 2.58 Mb(1C) and 112.73 ± 14.00 Mb(1C), respectively, depending on the different internal references. The results of this research will promote the related studies on the genomics and evolution of these two species.展开更多
It has been shown that duplicate genes on the X chromosome evolve much faster than duplicate genes on autosomes in Drosophila melanogaster. However, whether this phenomenon is general and can be applied to other speci...It has been shown that duplicate genes on the X chromosome evolve much faster than duplicate genes on autosomes in Drosophila melanogaster. However, whether this phenomenon is general and can be applied to other species is not known. Here we examined this issue in chicken that have heterogametic females （females have ZW sex chromosome）. We compared sequence divergence of duplicate genes on the Z chromosome with those on autosomes. We found that duplications on the Z chromosome indeed evolved faster than those on autosomes and show distinct patterns of molecular evolution from autosomal duplications. Examination of the expression of duplicate genes revealed an enrichment of duplications on the Z chromosome having male-biased expression and an enrichment of duplications on the autosomes having female-biased expression. These results suggest an evolutionary trend of the recruitment of duplicate genes towards reproduction-specific function. The faster evolution of duplications on Z than on the autosomes is most likely contributed by the selective forces driving the fixation of adaptive mutations on Z. Therefore, the common phenomena observed in both flies and chicken suggest that duplicate genes on sex chromosomes have distinct dynamics and are more influenced by natural selection than autosomal duplications, regardless of the kind of sex determination systems.展开更多
基金supported by the Ministry of Science and Higher Education of the Russian Federation(No.075-152021-1037,Internal No.15.BRK.21.0001)。
文摘The worldwide chicken gene pool encompasses a remarkable,but shrinking,number of divergently selected breeds of diverse origin.This study was a large-scale genome-wide analysis of the landscape of the complex molecular architecture,genetic variability,and detailed structure among 49 populations.These populations represent a significant sample of the world's chicken breeds from Europe(Russia,Czech Republic,France,Spain,UK,etc.),Asia(China),North America(USA),and Oceania(Australia).Based on the results of breed genotyping using the Illumina 60K single nucleotide polymorphism(SNP)chip,a bioinformatic analysis was carried out.This included the calculation of heterozygosity/homozygosity statistics,inbreeding coefficients,and effective population size.It also included assessment of linkage disequilibrium and construction of phylogenetic trees.Using multidimensional scaling,principal component analysis,and ADMIXTURE-assisted global ancestry analysis,we explored the genetic structure of populations and subpopulations in each breed.An overall 49-population phylogeny analysis was also performed,and a refined evolutionary model of chicken breed formation was proposed,which included egg,meat,dual-purpose types,and ambiguous breeds.Such a large-scale survey of genetic resources in poultry farming using modern genomic methods is of great interest both from the viewpoint of a general understanding of the genetics of the domestic chicken and for the further development of genomic technologies and approaches in poultry breeding.In general,whole genome SNP genotyping of promising chicken breeds from the worldwide gene pool will promote the further development of modern genomic science as applied to poultry.
基金supported by the China Animal Disease Prevention and Control Centerthe China Agriculture Research System Poultry-Related Science and Technology Innovation Team of Peking, China (CARS-PSTP)
文摘supported by the China Animal Disease Prevention and Control Center;the China Agriculture Research System Poultry-Related Science and Technology Innovation Team of Peking, China （CARS-PSTP）
基金supported by the National Natural Science Foundation of China (Nos.41176098 and 31372529)
文摘Flow cytometry(FCM) technique has been widely applied to estimating the genome size of various higher plants. However, there is few report about its application in algae. In this study, an optimized procedure of FCM was exploited to estimate the genome size of two eukaryotic algae. For analyzing Alexandrium catenella, an important red tide species, the whole cell instead of isolated nucleus was studied, and chicken erythrocytes were used as an internal reference. The genome size of A. catenella was estimated to be 56.48 ± 4.14 Gb(1C), approximately nineteen times larger than that of human genome. For analyzing Gracilariopsis lemaneiformis, an important economical red alga, the purified nucleus was employed, and Arabidopsis thaliana and Chondrus crispus were used as internal references, respectively. The genome size of Gp. lemaneiformis was 97.35 ± 2.58 Mb(1C) and 112.73 ± 14.00 Mb(1C), respectively, depending on the different internal references. The results of this research will promote the related studies on the genomics and evolution of these two species.
基金supported by the National Science Foundation of China (No. 30600064)the National Basic Research Program of China (973 Program) (No. 2007CB815702) to X.Lu
文摘It has been shown that duplicate genes on the X chromosome evolve much faster than duplicate genes on autosomes in Drosophila melanogaster. However, whether this phenomenon is general and can be applied to other species is not known. Here we examined this issue in chicken that have heterogametic females （females have ZW sex chromosome）. We compared sequence divergence of duplicate genes on the Z chromosome with those on autosomes. We found that duplications on the Z chromosome indeed evolved faster than those on autosomes and show distinct patterns of molecular evolution from autosomal duplications. Examination of the expression of duplicate genes revealed an enrichment of duplications on the Z chromosome having male-biased expression and an enrichment of duplications on the autosomes having female-biased expression. These results suggest an evolutionary trend of the recruitment of duplicate genes towards reproduction-specific function. The faster evolution of duplications on Z than on the autosomes is most likely contributed by the selective forces driving the fixation of adaptive mutations on Z. Therefore, the common phenomena observed in both flies and chicken suggest that duplicate genes on sex chromosomes have distinct dynamics and are more influenced by natural selection than autosomal duplications, regardless of the kind of sex determination systems.
