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KCNQ1 rs2237895 gene polymorphism increases susceptibility to type 2 diabetes mellitus in Asian populations 被引量:1
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作者 Dong-Xu Li Li-Ping Yin +4 位作者 Yu-Qi Song Nan-Nan Shao Huan Zhu Chen-Sen He Jiang-Jie Sun 《World Journal of Diabetes》 SCIE 2024年第3期552-564,共13页
BACKGROUND The association of single nucleotide polymorphism of KCNQ1 gene rs2237895 with type 2 diabetes mellitus(T2DM)is currently controversial.It is unknown whether this association can be gene realized across dif... BACKGROUND The association of single nucleotide polymorphism of KCNQ1 gene rs2237895 with type 2 diabetes mellitus(T2DM)is currently controversial.It is unknown whether this association can be gene realized across different populations.AIM To determine the association of KCNQ1 rs2237895 with T2DM and provide reliable evidence for genetic susceptibility to T2DM.METHODS We searched PubMed,Embase,Web of Science,Cochrane Library,Medline,Baidu Academic,China National Knowledge Infrastructure,China Biomedical Literature Database,and Wanfang to investigate the association between KCNQ1 gene rs2237895 and the risk of T2DM up to January 12,2022.Review Manager 5.4 was used to analyze the association of the KCNQ1 gene rs2237895 polymorphism with T2DM and to evaluate the publication bias of the selected literature.RESULTS Twelve case–control studies(including 11273 cases and 11654 controls)met our inclusion criteria.In the full population,allelic model[odds ratio(OR):1.19;95%confidence interval(95%CI):1.09–1.29;P<0.0001],recessive model(OR:1.20;95%CI:1.11–1.29;P<0.0001),dominant model(OR:1.27.95%CI:1.14–1.42;P<0.0001),and codominant model(OR:1.36;95%CI:1.15–1.60;P=0.0003)(OR:1.22;95%CI:1.10–1.36;P=0.0002)indicated that the KCNQ1 gene rs2237895 polymorphism was significantly correlated with susceptibility to T2DM.In stratified analysis,this association was confirmed in Asian populations:allelic model(OR:1.25;95%CI:1.13–1.37;P<0.0001),recessive model(OR:1.29;95%CI:1.11–1.49;P=0.0007),dominant model(OR:1.35;95%CI:1.20–1.52;P<0.0001),codominant model(OR:1.49;95%CI:1.22–1.81;P<0.0001)(OR:1.26;95%CI:1.16–1.36;P<0.0001).In non-Asian populations,this association was not significant:Allelic model(OR:1.06,95%CI:0.98–1.14;P=0.12),recessive model(OR:1.04;95%CI:0.75–1.42;P=0.83),dominant model(OR:1.06;95%CI:0.98–1.15;P=0.15),codominant model(OR:1.08;95%CI:0.82–1.42;P=0.60.OR:1.15;95%CI:0.95–1.39;P=0.14).CONCLUSION KCNQ1 gene rs2237895 was significantly associated with susceptibility to T2DM in an Asian population.Carriers of the C allele had a higher risk of T2DM.This association was not significant in non-Asian populations. 展开更多
关键词 Type 2 diabetes mellitus KCNQ1 rs2237895 Single nucleotide polymorphism Asian populations
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Evolutionary game dynamics of combining two different aspiration-driven update rules in structured populations
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作者 杨智昊 杨彦龙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期182-191,共10页
In evolutionary games,most studies on finite populations have focused on a single updating mechanism.However,given the differences in individual cognition,individuals may change their strategies according to different... In evolutionary games,most studies on finite populations have focused on a single updating mechanism.However,given the differences in individual cognition,individuals may change their strategies according to different updating mechanisms.For this reason,we consider two different aspiration-driven updating mechanisms in structured populations:satisfied-stay unsatisfied shift(SSUS)and satisfied-cooperate unsatisfied defect(SCUD).To simulate the game player’s learning process,this paper improves the particle swarm optimization algorithm,which will be used to simulate the game player’s strategy selection,i.e.,population particle swarm optimization(PPSO)algorithms.We find that in the prisoner’s dilemma,the conditions that SSUS facilitates the evolution of cooperation do not enable cooperation to emerge.In contrast,SCUD conditions that promote the evolution of cooperation enable cooperation to emerge.In addition,the invasion of SCUD individuals helps promote cooperation among SSUS individuals.Simulated by the PPSO algorithm,the theoretical approximation results are found to be consistent with the trend of change in the simulation results. 展开更多
关键词 evolutionary game dynamics aspiration-driven update structured populations
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Changes in the adult sex ratio of six duck species breeding populations over two decades
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作者 Monika Homolkova Petr Musil +4 位作者 Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar 《Avian Research》 SCIE CSCD 2024年第2期202-210,共9页
Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of research... Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered species.Species with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction risk.In this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and 2022.This evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in winter.We determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and males.In the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early 2020s.However,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population. 展开更多
关键词 Adult sex ratio Breeding population Population dynamics Red-listed species WATERFOWL Winter weather conditions
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Comparative Study of Genetic Structure and Genetic Diversity betweenWild and Cultivated Populations of Taxus cuspidata,Northeast China
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作者 Dandan Wang Xiaohong Li Yanwen Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期355-369,共15页
Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is... Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is,33 wild yews and 28 cultivated yews were used to analyze the differences and correlations of the kinship,genetic diversity,and genetic structure between them by specific length amplified fragment sequencing(SLAF-seq).Finally,470725 polymorphic SLAF tags and 58622 valid SNP markers were obtained.Phylogenetic analysis showed that 61 samples were classified into 2 clusters:wild populations and cultivated populations,and some wild yews were categorized into the cultivated populations;the genetic diversity analysis showed that the Nei diversity index of wild populations(0.4068)was smaller than that of cultivated populations(0.4414),and the polymorphic information content(PIC)of wild populations(0.2861)was smaller than that of cultivated populations(0.3309).The genetic differentiation analysis showed that the total populations of gene diversity(H_(t))of cultivated and wild populations were respectively 0.8159 and 0.5685,the coefficient of gene differentiation(G_(st))of cultivated and wild populations was respectively 0.3021 and 0.1068,and the gene flow(N_(m))(2.4967)of wild populations was larger than cultivated populations(0.8199).The molecular variance(AMOVA)revealed that inter-population variation accounted for 29.57%of the total genetic variation,while intra-population variation accounted for 70.42% of the total genetic variation(p<0.001),this suggested that the genetic variation in the T.cuspidata is mainly attributed to within-population factors.In conclusion,the genetic distance between geographical ecological groups of wild populations was generally smaller than that of cultivated populations,and the degree of genetic diversity and genetic differentiation was smaller than that of cultivated populations.As evident,the utilization of SLAF-seq technology enables efficient and accurate development of SNP markers suitable for genetic analysis of T.cuspidata species.These developed SNP markers can provide a molecular foundation for T.cuspidata breeding,construction of genetic maps,variety identification,and association analysis of agronomic traits. 展开更多
关键词 T.cuspidata SLAF-seq SNP wild population cultivated population genetic structure
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Photosynthetic response to a winter heatwave in leading and trailing edge populations of the intertidal red alga Corallina offi-cinalis(Rhodophyta)
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作者 Regina Kolzenburg Federica Ragazzola +3 位作者 Laura Tamburello Katy R.Nicastro Christopher D.McQuaid Gerardo I.Zardi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期70-77,共8页
Marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem level.Thermal conditions experienced by marine organisms across their distribution,particularly towards... Marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem level.Thermal conditions experienced by marine organisms across their distribution,particularly towards the equator,are likely to approach their physiological limits,resulting in extensive mortality and subsequent changes at the population level.Populations at the margins of their species’distribution are thought to be more sensitive to climate-induced environmental pressures than central populations,but our understanding of variability in fitness-related physiological traits in trailing versus leading-edge populations is limited.In a laboratory simulation study,we tested whether two leading(Iceland)and two trailing(Spain)peripheral populations of the intertidal macroalga Corallina officinalis display different levels of maximum potential quantum efficiency(Fv/Fm)resilience to current and future winter MHWs scenarios.Our study revealed that ongoing and future local winter MHWs will not negatively affect leading-edge populations of C.officinalis,which exhibited stable photosynthetic efficiency throughout the study.Trailing edge populations showed a positive though non-significant trend in photosynthetic efficiency throughout winter MHWs exposure.Poleward and equatorward populations did not produce significantly different results,with winter MHWs having no negative affect on Fv/Fm of either population.Additionally,we found no long-term regional or population-level influence of a winter MHWs on this species’photosynthetic efficiency.Thus,we found no statistically significant difference in thermal stress responses between leading and trailing populations.Nonetheless,C.officinalis showed a trend towards higher stress responses in southern than northern populations.Because responses rest on a variety of local population traits,they are difficult to predict based solely on thermal pressures. 展开更多
关键词 marginal population coralline algae climate change ECOPHYSIOLOGY photophysiology MACROALGAE FV/FM
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Multi-environment BSA-seq using large F3 populations is able to achieve reliable QTL mapping with high power and resolution: An experimental demonstration in rice
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作者 Yan Zheng Ei Ei Khine +9 位作者 Khin Mar Thi Ei Ei Nyein Likun Huang Lihui Lin Xiaofang Xie Min Htay Wai Lin Khin Than Oo Myat Myat Moe San San Aye Weiren Wu 《The Crop Journal》 SCIE CSCD 2024年第2期549-557,共9页
Bulked-segregant analysis by deep sequencing(BSA-seq) is a widely used method for mapping QTL(quantitative trait loci) due to its simplicity, speed, cost-effectiveness, and efficiency. However, the ability of BSA-seq ... Bulked-segregant analysis by deep sequencing(BSA-seq) is a widely used method for mapping QTL(quantitative trait loci) due to its simplicity, speed, cost-effectiveness, and efficiency. However, the ability of BSA-seq to detect QTL is often limited by inappropriate experimental designs, as evidenced by numerous practical studies. Most BSA-seq studies have utilized small to medium-sized populations, with F2populations being the most common choice. Nevertheless, theoretical studies have shown that using a large population with an appropriate pool size can significantly enhance the power and resolution of QTL detection in BSA-seq, with F_(3)populations offering notable advantages over F2populations. To provide an experimental demonstration, we tested the power of BSA-seq to identify QTL controlling days from sowing to heading(DTH) in a 7200-plant rice F_(3)population in two environments, with a pool size of approximately 500. Each experiment identified 34 QTL, an order of magnitude greater than reported in most BSA-seq experiments, of which 23 were detected in both experiments, with 17 of these located near41 previously reported QTL and eight cloned genes known to control DTH in rice. These results indicate that QTL mapping by BSA-seq in large F_(3)populations and multi-environment experiments can achieve high power, resolution, and reliability. 展开更多
关键词 BSA-seq QTL mapping Large F3 population Multi-environment experiment Cross-validation
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Dependence of Rydberg-atom-based sensor performance on different Rydberg atom populations in one atomic-vapor cell
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作者 武博 姚佳伟 +2 位作者 吴逢川 安强 付云起 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期365-370,共6页
The atomic-vapor cell is a vital component for Rydberg atomic microwave sensors,and impacts on overall capability of Rydberg sensors.However,the conventional analysis approach on effect of vapor-cell length contains t... The atomic-vapor cell is a vital component for Rydberg atomic microwave sensors,and impacts on overall capability of Rydberg sensors.However,the conventional analysis approach on effect of vapor-cell length contains two implicit assumptions,that is,the same atomic population density and buffer gas pressure,which make it unable to accurately capture actual response about effect of Rydberg-atom-based sensor performance on different Rydberg atom populations.Here,utilizing a stepped cesium atomic-vapor cell with five different dimensions at the same atomic population density and buffer gas pressure,the height and full width at half maximum of electromagnetically induced transparency(EIT)signal,and the sensitivity of the atomic superheterodyne sensor are comprehensively investigated under conditions of the same Rabi frequencies(saturated laser power).It is identified that EIT signal height is proportional to the cell length,full width at half maximum and sensitivity grow with the increment of cell length to a certain extent.Employing the coherent integration signal theory and atomic linear expansion coefficient method,theoretical analysis of the EIT height and sensitivity are further investigated.The results could shed new light on understanding and design of ultrahigh-sensitivity Rydberg atomic microwave sensors and find promising applications in quantum measurement,communication,and imaging. 展开更多
关键词 Rydberg atom population Rydberg-atom-based receiver stepped atomic-vapor cell
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Analysis of Genetic Structure of Natural Populations of Castanopsis fargesii by RAPDs 被引量:12
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作者 朱其慧 潘惠新 +3 位作者 诸葛强 尹佟明 邹惠渝 黄敏仁 《Acta Botanica Sinica》 CSCD 2002年第11期1321-1326,共6页
Genetic diversity and population genetic structure in 188 individuals from five natural populations of Castampsis fargesii Franch. were studied by RAPD markers. Three hundred and eighty-five loci were identified with ... Genetic diversity and population genetic structure in 188 individuals from five natural populations of Castampsis fargesii Franch. were studied by RAPD markers. Three hundred and eighty-five loci were identified with 41 oligonucleotide primers, out of which 157 loci were polymorphic and accounted for 40.78% of total genetic diversity at species level. Shannon's indices of diversity (I) and Nei's gene diversity ( h) were 0.459 7 and 0.296 at the species level, respectively. The result showed that genetic variation of C. fargesii populations mainly existed within populations. Genetic differentiation (Hsp-hpop)/Hsp estimated with Shannon's index of diversity and coefficient of gene differentiation (Gst) were 0.047 6 and 0.042 9 respectively, which were confirmed by the analysis of molecular variance (AMOVA). Therefore, it is apparent that within-population variation accounted for 94.97% and among-populations variation accounted for only 5.03% of the total genetic diversity. AMOVA also indicated that there was significant differentiation among populations as well as among individuals within a population. 展开更多
关键词 Castanopsis fargesii natural populations RAPD genetic structure
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Multi Location Field Evaluation of BC1F2 Sorghum Populations for Striga Resistance in Niger
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作者 Ousseini Ardaly Abdou Aissata Mamadou Ibrahim +2 位作者 Yaw Eleblu John Saviour Ofori Kwadwo Ousmane Zakari Moussa 《American Journal of Plant Sciences》 CAS 2024年第10期1010-1021,共12页
In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected... In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected by biotic and abiotic constraints. Among those constraints, striga has a high impact on yield. In fact, to survive, farmers are growing their local preferred sorghum varieties wish is highly sensible to the weed. Striga management is a challenge that requires a permanent solution. In addition, the development of high-yielding Striga resistant genotypes will be appreciated by farmers. The development of striga resistance will be based on the breeding population performances under farmer’s diverse environmental conditions adaptation. The main objective of this study is to evaluate two breeding populations for striga resistance in two different environments at Boulke and Dibissou in Tahoua region, to identify the early and high-yielding striga tolerant genotypes under natural infestation. 展开更多
关键词 Striga Resistance SORGHUM Breeding Population Multi Environment
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Research on the Renovation of Rural Buildings Suitable for Aging Populations Based on Cross-Analysis
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作者 Zhengming Zhu Feiyan Li 《Journal of Architectural Research and Development》 2024年第6期17-23,共7页
Based on the intersection of“Implementing the National Strategy to Actively Cope with Population Aging”and“Guiding Opinions on Future Rural Construction”in Zhejiang Province,this study constructed the evaluation i... Based on the intersection of“Implementing the National Strategy to Actively Cope with Population Aging”and“Guiding Opinions on Future Rural Construction”in Zhejiang Province,this study constructed the evaluation index system of rural age-appropriate building space.This is done by analyzing the current situation locally and internationally,summarizing the existing problems,and optimizing countermeasures.The cross-analysis method is adopted by fully listening to the opinions of the elderly and introducing a professional team to transform the physical,psychological,and rural natural environment of the elderly.The renovation strategies of building layout,indoor and outdoor space,and supporting facilities for the elderly are put forward.Looking to the future,including the application of intelligent technology,the development of a community pension model,and multi-party cooperation,it aims to create a comfortable,safe,and convenient living environment for rural elderly people,improve the quality of life,promote rural revitalization and actively respond to the challenges of population aging. 展开更多
关键词 Cross-analysis China Aging population Rural building renovation
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Genetic Polymorphism of Mitochondrial DNA in Dong,Gelao,Tujia,and Yi Ethnic Populations from Guizhou,China
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作者 李彬彬 钟复光 +5 位作者 易红生 王先然 李良芳 王丽兰 齐晓岚 吴立甫 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第9期800-811,共12页
To reveal the genetic structures and relationships of the four ethnic populations from the maternal inheritance and explore the origins and migrations of nationalities, the genetic polymorphism of mtDNA in Dong, Gelao... To reveal the genetic structures and relationships of the four ethnic populations from the maternal inheritance and explore the origins and migrations of nationalities, the genetic polymorphism of mtDNA in Dong, Gelao, Tujia, and Yi populations from Guizhou was studied by direct sequencing of hypervariable segment Ⅰ (HVS Ⅰ ) and PCR-RFLP of coding region. Thirty-seven (sub-) haplogroups were identified in the classification tree of mtDNA haplogroups. Haplogroup distributions and principal component (PC) analysis showed that the Dong has high frequencies of south-prevalent haplogroups, which indicates that it is a typically southern population. The Yi harbors high frequencies of the south-prevalent and northern-prevalent haplogroups, which demonstrates that it inherits the maternal characteristics from both southern and northern populations. The Yi and Gelao cluster together, the reason for which might be that their ancestries frequently underwent gene exchanges and mixtures. 展开更多
关键词 ethnic populations in Guizhou mitochondrial DNA POLYMORPHISM
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Effects of Nitrogen Fertilizer on Rhizosphere Microbial Populations under Cotton Intercropped with Red Date in Arid Desert Oasis of Southern Xinjiang
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作者 汤秋香 石大伟 +7 位作者 林涛 高文伟 田立文 郭仁松 李玉 叶强涛 林毅 徐海东 《Agricultural Science & Technology》 CAS 2014年第2期207-211,309,共6页
[Objective]This study aimed to determine the number of microorganisms of cotton rhizosphere in a soil at various amounts of applied nitrogen fertilizer in a red date-cotton intercropping system. [Method] In the field ... [Objective]This study aimed to determine the number of microorganisms of cotton rhizosphere in a soil at various amounts of applied nitrogen fertilizer in a red date-cotton intercropping system. [Method] In the field experiment, nitrogen fer-tilizer was applied at 0, 150, 300, 450, 600, and 750 kg/hm2, respectively. The dy-namic changes of the populations of bacteria, fungi and actinomycetes at the rhizo-sphere of cotton intercropped with red date were investigated. [Result] Microbial populations significantly increased at nitrogen fertilizer of 300 and 450 kg/hm2 during bud, flowering and bol opening periods. The numbers of bacteria and actinomycetes were higher during flowering and bol opening stages than at bud stage. The num-ber of fungi slightly changed during the entire growth period. Appropriate amount of nitrogen fertilizer (300 to 600 kg/hm2) was favorable to the survival of the microor-ganisms in the soil under the intercropping system. [Conclusion] The study provides a guideline for screening and determining the optimum amount of applied nitrogen fertilizer. 展开更多
关键词 Red date and cotton intercropping system Nitrogen fertilizer Rhizo-sphere soil Microbial populations
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Genetic Diversity in Wild Populations of Poacynum hendersonii from Inland Arid Regions of Northwest China 被引量:21
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作者 赵金凤 张卫明 +3 位作者 彭雪梅 唐泽紫 顾龚平 陆长梅 《Agricultural Science & Technology》 CAS 2008年第4期39-43,共5页
[Objective] Study on the genetic diversity in wild populations of Poacynum hendersonii.[Method] Random amplified polymorphic DNA(RAPD)technique was employed to analyze the genetic diversity in five wild populations of... [Objective] Study on the genetic diversity in wild populations of Poacynum hendersonii.[Method] Random amplified polymorphic DNA(RAPD)technique was employed to analyze the genetic diversity in five wild populations of P.hendersonii sampled from Xinjiang,Gansu and Qinghai provinces.[Result] Totally 165 clear and repeatable bands were generated in RAPD reaction by using 20 primers screened from 80 primers,of which 110 were polymorphic,accounting for 66.67%.At species level,Nei's gene diversity index(H),Shannon's information index(I)and genetic differentiation coefficient(Gst)were 0.220 5,0.304 7 and 0.908 2,respectively.P.hendersonii germplasm resources share a high level of genetic diversity,and genetic differentiation mainly exists among the populations.Results from genetic distances and cluster analysis showed that relationships among P.hendersonii populations were to some extent related with their geographical and climatic characters.[Conclusion] This study suggests that the conservation of P.hendersonii should focus on the protection of many populations,particularly the Qinghai population. 展开更多
关键词 Poacynum hendersonii WILD POPULATION GENETIC diversity RAPD
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Genetic differentiations between randomly and selectively bred pig populations in Yunnan,China 被引量:10
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作者 亐开兴 吴桂生 +4 位作者 苟潇 严达伟 连林生 Mumtaz Baig 张亚平 《Zoological Research》 CAS CSCD 北大核心 2011年第3期255-261,共7页
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 ... 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. 展开更多
关键词 Yunnan pig breeds Genetic diversity Randomly bred population Selectively bred population
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Microsatellite Variations Among Four Populations of Eriocheir sinensis 被引量:21
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作者 马海涛 常玉梅 +1 位作者 于冬梅 孙效文 《Zoological Research》 CAS CSCD 北大核心 2007年第2期126-133,共8页
Using microsatellite markers, we analysed genetic polymorphism in four populations of Eriocheir sinensis, sampled from Jiangsu, Anhui, Liaoning and Tianjin. Twenty-four pairs of primers were used to amplify the target... Using microsatellite markers, we analysed genetic polymorphism in four populations of Eriocheir sinensis, sampled from Jiangsu, Anhui, Liaoning and Tianjin. Twenty-four pairs of primers were used to amplify the target fragments ranging from 80 bp to 445 bp, which included 16 pairs designed in our laboratory and eight pairs published internationally. Two to 10 alleles per locus in four populations were amplified, and there were 155 alleles in all populations. The average number of alleles per locus was 6.458. The average number of effective alleles per locus (Ne) was 4.349l to 4.7234; the average observed heterozygosity (Ho) was 0.5690 to 0.6722; and the average expected heterozygosity (He) was 0.7238 to 0.7546. Hardy-Weinberg equilibrium analysis (Z2 test, P 〈 0.05) revealed that seven loci in the four populations were in equilibrium. The genetic distances between the four populations were calculated and revealed that the Anhui, Jiangsu and Tianjin crabs belong to a Yangtse River population, while the Liaohe crabs form another branch. 展开更多
关键词 Eriocheir sinensis MICROSATELLITE Population polymorphism
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Genetic Structure of Three Populations of Oxya chinensis in Shanxi,China 被引量:17
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作者 韩焱 段毅豪 +1 位作者 马恩波 乔海晅 《Zoological Research》 CAS CSCD 北大核心 2002年第1期76-80,共5页
Starch gel electrophoresis was used to analyze genetic structure of three populations of Oxya chinensis from Shanxi Province,China.Four allozyme polymorphic loci (MDH-1,MDH-2,LDH,ME) were found.The data suggest that t... Starch gel electrophoresis was used to analyze genetic structure of three populations of Oxya chinensis from Shanxi Province,China.Four allozyme polymorphic loci (MDH-1,MDH-2,LDH,ME) were found.The data suggest that two populations of O.chinensis about 41 kilometers apart are genetically similar,but differentiated from the third population with a geographic distance of 357 kilometers.However,the heterozygosity levels of those two genetically similar populations were much different.The Nei's genetic distance between two geographically close populations is 0.068,which is much smaller than those of geographically distant populations (0.23 in average).The observed overlap of geographical distance and genetic distance implies that for O.chinensis population divergence may correlate with geographic isolation. 展开更多
关键词 Oxya chinensis ALLOZYME Population genetics SHANXI
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Microsatellite DNA Marker Analysis of Genetic Diversity in Wild Common Carp (Cyprinus carpio L.) Populations 被引量:6
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作者 李大宇 康大海 +2 位作者 殷倩茜 孙效文 梁利群 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第11期984-993,共10页
Thirty microsatellite loci were used for analyzing six wild populations of common carp (Cyprinus carpio L.). Observed (Ho) and expected (He) heterozygosity values, polymorphic information content (PIC), and nu... Thirty microsatellite loci were used for analyzing six wild populations of common carp (Cyprinus carpio L.). Observed (Ho) and expected (He) heterozygosity values, polymorphic information content (PIC), and number of effective alleles (Ae) were all detected. Genetic similarity index and genetic distance were computed based on the allele frequency. The Hardy-Weinberg Equilibrium was checked according to the test of χ^2. Genetic differentiation and hierarchical partition of genetic diversity were evaluated by FST and Nm. A clustering dendrograrn was made based on the results of UPGMA methods using the PHYLIP software package (version 3.63). There were totally 8,136 fragments ranging from 125 bp to 414 bp in length. Three to thirteen alleles were amplified in 30 loci and 210 alleles in all six populations. The average number of alleles in each locus was seven. The result showed that 1) the level of genetic variability was moderate in the six populations. Polymorphic information contents of the six wild common carp populations were 0.44, 0.52, 0.53, 0.57, 0.63, and 0.64 respectively. Effective alleles were from 1.04 to 4.72, the average numbers in each population were 2.19, 2.60, 2.42, 2.43, 2.45, and 2.33. The average expected heterozygosity values were 0.50, 0.59, 0.56, 0.56, 0.57, and 0.54 respectively; 2) the highest genetic similarity index that came from the populations of BR and ZL was 0.8511 and the lowest index was 0.6688, and it came from the populations of BR and HN. There was a correlation between the clustering result and the geographical distribution. 展开更多
关键词 molecular marker MICROSATELLITE population variety common carp
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Genetic Analysis of Cultured and Wild Populations of Mytilus coruscus Based on Mitochondrial DNA 被引量:18
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作者 沈玉帮 李家乐 冯冰冰 《Zoological Research》 CAS CSCD 北大核心 2009年第3期240-246,共7页
DNA sequences from the mitochondrial gene cytochrome oxidase subunit I (mtDNA CO I) were used to estimate the genetic variability in two wild populations and two cultured populations of the hard shelled mussel, Myti... DNA sequences from the mitochondrial gene cytochrome oxidase subunit I (mtDNA CO I) were used to estimate the genetic variability in two wild populations and two cultured populations of the hard shelled mussel, Mytilus coruscus. Thirty haplotypes were identified in the four populations. The cultured populations exhibited a lower number of haplotypes and genetic diversity than those of the wild populations, suggesting that a small number of effective founding breeders contributed to the genetic variation of the cultured populations. No significant differentiation was observed between the cultured population and local wild population, implying that persistent gene flow occurred in these populations. This genetic survey is intended as a baseline for future genetic monitoring of M. coruseus aquaculture stocks. 展开更多
关键词 Mytilus coruscus Population differentiation Genetic diversity mtDNA COI gene
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QTL IciMapping:Integrated software for genetic linkage map construction and quantitative trait locus mapping in biparental populations 被引量:212
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作者 Lei Meng Huihui Li +1 位作者 Luyan Zhang Jiankang Wang 《The Crop Journal》 SCIE CAS CSCD 2015年第3期269-283,共15页
QTL Ici Mapping is freely available public software capable of building high-density linkage maps and mapping quantitative trait loci(QTL) in biparental populations. Eight functionalities are integrated in this softwa... QTL Ici Mapping is freely available public software capable of building high-density linkage maps and mapping quantitative trait loci(QTL) in biparental populations. Eight functionalities are integrated in this software package:(1) BIN: binning of redundant markers;(2) MAP: construction of linkage maps in biparental populations;(3) CMP: consensus map construction from multiple linkage maps sharing common markers;(4) SDL: mapping of segregation distortion loci;(5) BIP: mapping of additive, dominant, and digenic epistasis genes;(6) MET: QTL-by-environment interaction analysis;(7) CSL: mapping of additive and digenic epistasis genes with chromosome segment substitution lines; and(8) NAM: QTL mapping in NAM populations. Input files can be arranged in plain text, MS Excel 2003, or MS Excel 2007 formats. Output files have the same prefix name as the input but with different extensions. As examples, there are two output files in BIN, one for summarizing the identified bin groups and deleted markers in each bin, and the other for using the MAP functionality. Eight output files are generated by MAP, including summary of the completed linkage maps, Mendelian ratio test of individual markers, estimates of recombination frequencies, LOD scores, and genetic distances, and the input files for using the BIP, SDL,and MET functionalities. More than 30 output files are generated by BIP, including results at all scanning positions, identified QTL, permutation tests, and detection powers for up to six mapping methods. Three supplementary tools have also been developed to display completed genetic linkage maps, to estimate recombination frequency between two loci,and to perform analysis of variance for multi-environmental trials. 展开更多
关键词 Biparental populations MAP CONSTRUCTION QTL MAPPING SOFTWARE
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Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis 被引量:6
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作者 陈少瑜 赵文书 王炯 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期273-276,337,共4页
Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis were examined by means of electrophoresis technique. Analysis of 9 enzyme systems including 16 loci showed that ... Genetic diversity and genetic differentiation of natural populations of Pinus kesiya var. langbinanensis were examined by means of electrophoresis technique. Analysis of 9 enzyme systems including 16 loci showed that all the three natural popu-lations of the pine were high in genetic diversity but low in inter-population genetic differentiation. The proportion of polymorphic loci is 0.667, with each locus holding 2.13 alleles, averagely. The average expected and observed heterozygosity was 0.288 and 0.197, respectively. The gene differentiation among populations was 0.052, but the mean genetic distance was only 0.015. 展开更多
关键词 Pinus kesiya var. langbinanensis Natural population ISOZYME Genetic diversity Genetic differentiation
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