Shallow Genetic Structure of Pholis fangi in Bohai Sea and Yellow Sea Inferred from mt DNA Control Region

Pholis fangi is an ecologically important fish species inhabiting Chinese coastal waters of Yellow Sea and Bohai Sea. To investigate the genetic diversity and population genetic structure of P. fangi, a fragment of 487 bp in the first hypervariable region (HVR-1) of the mitochondrial DNA (mtDNA) control region was sequenced for 181 individuals collected from Bohai Sea and Yel- low Sea. A total of 18 polymorphic sites were detected, which defined 25 haplotypes. A moderate level of haplotype diversity (h = 0.7052) and a low level of nucleotide diversity (π= 0.0028) were detected. Both the phylogenetic tree and the haplotype network showed no significant genealogical structure difference among sampling locations. Pairwise FST comparison and hierarchical mo- lecular variance analysis (AMOVA) revealed that no significant genetic structure difference existed throughout the investigated re- gions, suggesting a high gene exchange among different populations. The results of neutrality test and mismatch distribution analysis indicated that a late Pleistocene population expansion (38000 127000 years ago) happened. Seasonal schooling migration may con- tribute to the genetically homogeneous population structure of the species.

Satellite Constellation Design with Multi-Objective Genetic Algorithm for Regional Terrestrial Satellite Network

Constellations design for regional terrestrial-satellite network can strengthen the coverage for incomplete terrestrial cellular network. In this paper, a regional satellite constellation design scheme with multiple feature points and multiple optimization indicators is proposed by comprehensively considering multi-objective optimization and genetic algorithm, and "the Belt and Road" model is presented in the way of dividing over 70 nations into three regular target areas. Following this, we formulate the optimization model and devise a multi-objective genetic algorithm suited for the regional area with the coverage rate under simulating, computing and determining. Meanwhile, the total number of satellites in the constellation is reduced by calculating the ratio of actual coverage of a single-orbit constellation and the area of targets. Moreover, the constellations' performances of the proposed scheme are investigated with the connection of C++ and Satellite Tool Kit(STK). Simulation results show that the designed satellite constellations can achieve a good coverage of the target areas.

A Method for Upscaling Genetic Parameters of CERES-Rice in Regional Applications

To upscale the genetic parameters of CERES-Rice in regional applications, Jiangsu Province, the second largest rice producing province in China, was taken as an example. The province was divided into four rice regions with different rice variety types, and five to six sites in each region were selected. Then the eight genetic parameters of CERES-Rice, particularly the four parameters related to the yield, were modified and validated using the Trial and Error Method and the local statistical data of rice yield at a county level from 2001 to 2004, combined with the regional experiments of rice varieties in the province as well as the local meteorological and soil data （Method 1）. The simulated results of Method 1 were compared with those of other three traditional methods upscaling the genetic parameters, i.e., using one-site experimental data from a local representative rice variety （Method 2）, using local long-term rice yield data at a county level after deducting the trend yield due to progress of science and technology （Method 3）, and using rice yield data at a super scale, such as provincial, ecological zone, country or continent levels （Method 4）. The results showed that the best fitness was obtained by using the Method 1. The coefficients of correlation between the simulated yield and the statistical yield in the Method 1 were significant at 0.05 or 0.01 levels and the root mean squared error （RMSE） values were less than 9% for all the four rice regions. The method for upscaling the genetic parameters of CERES-Rice presented is not only valuable for the impact studies of climate change, but also favorable to provide a methodology for reference in crop model applications to the other regional studies.

Genetic Analysis of the P1 Region of Human Enterovirus 71 Strains and Expression of the 55 F StrainVP1 Protein

Enterovirus 71 （EV71） is a member of the Entero-virus genus of the Picomaviridae family and is the major cause of Hand, foot, and mouth disease （HFMD） in children. Different strains from Gansu were cloned and the P1 protein was sequenced and analysed. Results indicate that there are three kinds of EV71 infections prevalent in Gansu. The VP 1 protein from one of these strains, 55F, was expressed. The recombinant protein was expressed with high level and reacted specifically with the EV71 patient antibody, the recombinant protein was also applied to raise antiserum in rabbits and after the fourth injection a high titer of antiserum was detected by ELISA assay. These data are useful for further clarification of prevalent EV71 strains in the north of China at the molecular level and provide a basis for EV71 diagnosis.

Population Genetic Analysis of Sillago nigrofasciata (Perciformes:Sillaginidae) Along the Coast of China by Sequencing Mitochondrial DNA Control Region

Sillago nigrofasciata, a small to moderate size nearshore species, is newly found along the eastern and southern coasts of China. The present study is carried out in order to analyze the population genetics of the S. nigrofasciata. The control region sequence of mitochondrial DNA revealing 73 haplotypes were obtained from 162 individuals collected at 8 locations along the coast of China. The whole S. nigrofasciata population along the coast of China showed a low nucleotide diversity(0.012) and a high population diversity(haplotype diversity)(0.943), and all the 8 local populations showed low nucleotide diversities(0.014 – 0.001), suggesting the protective measures are effective. The haplotypes of the 8 local populations were widely distributed in haplotype network diagram and neighbor-joining phylogenetic tree, while no branch associating with sampling locations was detected. Recent gene flow analysis showed asymmetric gene exchanges among local populations. The pairwise FST values and unweighted pair-group method with arithmetic mean(UPGMA) tree revealed a certain amount of genetic difference among local populations. Moreover, analysis of molecular variance(AMOVA) reflected genetic differences between hypothetical subdivision groups. Neutral test and mismatch distribution of pairwise nucleotide suggested S. nigrofasciata may have experienced recent population expansion events. The historical geographic events associating with ice age may be the main explanation to the heterogeneity among local populations with short geographic distances, and the homogeneity among local populations with long geographic distances.

The Genetic Structure and Diversity of Repomucenus curvicornis Inhabiting Liaoning Coast Based on Mitochondrial COⅠ Gene and Control Region

[Object] This study was conducted to explore the genetic diversity and structure of the wild Repomucenus curvicornis inhabiting Liaoning Coast, China. [Method] The mitochondrial COⅠ gene and control region（CR） were PCR amplified from the wild R. curvicornis populations from the Liaodong Bay（n=22） and the northern Yellow Sea（n=18）, sequenced and analyzed for genetic diversity. [Result] The contents of A, T, C and G of 624 bp COⅠ gene were 24.09%, 31.04%, 25.28%, and 19.59%, and those of 460 bp CR fragment were 32.96%, 32.80%, 14.86% and 19.38%, respectively. The total number of variable sites, average number of nucleotide differences（ k）, haplotype diversity（H） and nucleotide diversity（π） based on COⅠ gene were 38, 4.67,（0.96±0.02） and（0.007 5±0.004 2）, and those based on CR fragment were 26, 3.35,（0.97 ±0.02） and（0.007 3±0.004 3）, respectively. Based on mitochondrial COⅠ gene and CR, the genetic diversity of Liaodong Bay population was lower than that of the northern Yellow Sea population. The AMOVA analysis based on CR fragments revealed almost significant genetic divergence between the Liaodong Bay and the northern Yellow Sea populations, while there was no significant genetic divergence based on COⅠ gene. The results showed that CR and COⅠ gene are effective molecular markers for detecting the genetic diversity of R. curvicornis population, while CR is more reliable than COⅠ gene in detecting the genetic structure. [Conclusion] CR is an appropriate marker for genetic analysis of marine fish population.

Genetic map construction and functional characterization of genes within the segregation distortion regions(SDRs)in the F_(2:3) populations derived from wild cotton species of the D genome

Background:Segregation distortion(SD)is a common phenomenon among stable or segregating populations,and the principle behind it still puzzles many researchers.The F2:3 progenies developed from the wild cotton species of the D genomes were used to investigate the possible plant transcription factors within the segregation distortion regions(SDRs).A consensus map was developed between two maps from the four D genomes,map A derived from F2:3 progenies of Gossypium klotzschianum and G.davidsonii while Map B from G.thurberi and G.trilobum F2:3 generations.In each map,188 individual plants were used.Results:The consensus linkage map had 1492 markers across the 13 linkage groups with a map size of 1467.445 cM and an average marker distance of 1.0370 cM.Chromosome D502 had the highest percentage of SD with 58.6%,followed by Chromosome D507 with 47.9%.Six thousand and thirty-eight genes were mined within the SDRs on chromosome D502 and D507 of the consensus map.Within chromosome D502 and D507,2308 and 3730 genes were mined,respectively,and were found to belong to 1117 gourp out of which 622 groups were common across the two chromosomes.Moreover,genes within the top 9 groups related to plant resistance genes(R genes),whereas 188 genes encoding protein kinase domain(PF00069)comprised the largest group.Further analysis of the dominant gene group revealed that 287 miRNAs were found to target various genes,such as the gra-miR398,gramiR5207,miR164a,miR164b,miR164c among others,which have been found to target top-ranked stress-responsive transcription factors such as NAC genes.Moreover,some of the stress-responsive cis-regulatory elements were also detected.Furthermore,RNA profiling of the genes from the dominant family showed that higher numbers of genes were highly upregulated under salt and osmotic stress conditions,and also they were highly expressed at different stages of fiber development.Conclusion:The results indicated the critical role of the SDRs in the evolution of the key regulatory genes in plants.

Dissecting the key genomic regions underlying high yield potential in common wheat variety‘Kenong 9204’

The foundation parents play key roles in the genetic improvement of both yield potential and end-use quality in wheat.Characterizing the genetic basis that underlies certain beneficial traits in the foundation parents will provide theoretical reference for molecular breeding by a design approach.‘Kenong 9204’(KN9204)is a candidate foundation parent characterized by ideotype,high yield potential,and particularly high nitrogen fertilizer utilization.To better understand the genetic basis of its high yield potential,high throughput whole-genome re-sequencing(10×)was performed on KN9204,its parental lines and its derivatives.A high-resolution genetic composition map of KN9204 was constructed,which showed the parental origin of the favorable genomic segments based on the identification of excellent yield-related quantitative trait loci(QTL)from a bi-parental mapping population.Xiaoyan 693(XY693),a wheat–Thinopyrum ponticum partial amphidiploid,contributed a great deal to the high yield potential of KN9204,and three major stable QTLs from XY693 were fine mapped.The transmissibility of key genomic segments from KN9204 to its derivatives were delineated,indicating that haplotype blocks containing beneficial gene combinations were conserved along with directional selection by breeders.Evidence for selection sweeps in the breeding programs was identified.This study provides a theoretical reference for the breeding of high-yield wheat varieties by a molecular design approach.

鄂尔多斯地区妊娠早期女性MTHFR C677T基因多态性与同型半胱氨酸的关系分析

目的 通过对鄂尔多斯地区妊娠早期女性MTHFR C677T基因多态性与同型半胱氨酸进行分析,明确MTHFR C677T基因多态性分布特点及二者之间的相关性,为科学指导妊娠期叶酸补充及预防出生缺陷提供遗传学依据。方法 选取2022年9月至2023年9月在鄂尔多斯市中心医院妇科门诊建档并进行妊娠早期检查的602例汉族妊娠早期女性作为研究对象,所有患者采集血液标本,采用PCR芯片杂交法检测MTHFR C677T基因多态性、生化酶循环法检测同型半胱氨酸水平,统计分析MTHFR C677T位点基因型与等位基因频率及与同型半胱氨酸的关系。结果 MTHFR C677T基因多态性CC、CT和TT型的检出频率分别为23.6%、47.5%、28.9%,等位基因C、T的检出频率分别为47.3%和52.7%,与上海、温州、眉山、南宁等地区汉族女性相比差异均有统计学意义(P<0.05),但与西安地区汉族女性相比差异均无统计学意义(P>0.05)。TT基因型孕妇血清同型半胱氨酸水平均高于CC和CT基因型孕妇,CT基因型孕妇血清同型半胱氨酸水平高于CC基因型孕妇(P<0.05)。MTHFR C677 T位点CT和TT基因型均为该地区妊娠早期女性发生高同型半胱氨酸血症的危险因素,分别为CC基因型的2.80倍和8.07倍,且差异均有统计学意义(P<0.05)。结论 鄂尔多斯汉族妊娠早期女性MTHFR C677T基因多态性分布具有地区特点,且与同型半胱氨酸水平有一定联系,妊娠期根据不同基因型制订个性化的叶酸补充方案对于预防出生缺陷具有重要意义。

苏州—无锡—常州地区地面沉降及地裂缝防控研究

苏州—无锡—常州(苏锡常)地区曾是中国地面沉降灾害最严重的地区之一,从20世纪70年代开始发生地面沉降,随之因差异沉降诱发地裂缝灾害,21世纪以来沉降速率逐年趋缓,部分地区出现区域性的地面回弹,独特的地面沉降发展历程为全面解读地面沉降提供了理想的窗口。为揭示苏锡常地区地面沉降生命周期过程及其驱动机制,利用长时间序列、大区域尺度的三维渗流、应力、应变多场监测数据以及物理试验模型、数值模拟等技术对区域地面沉降与地裂缝宏观演变规律、成因机理进行综合分析。研究结果显示:苏锡常地区地面沉降经历了发生、快速发展、趋缓、滞后和反弹5个阶段;地面沉降与地下水开采密切相关,其地层变形主要来自于地下水开采导致的含水层和弱透水层的压密释水,主采含水砂层及相邻隔水层为沉降主要贡献层,并识别了地层压缩、回弹的时空演变特征及其对地面沉降的贡献;地裂缝是地面沉降发展到一定阶段后所产生的次生地质灾害,其空间展布及成灾时间与地下水水位、地面沉降、基岩起伏变化以及土层结构差异等因素密切相关,提出了驱动地裂缝演化的压—拉—剪—弹物理过程,识别出了地裂缝发生的触发机制和临界条件。同时建立了以地质钻孔全断面光纤监测为特色、多种技术方法融合的“天-空-地”立体化、地下水-地面沉降-地裂缝协同的监测体系,为地面沉降防控提供科学、详细的数据支撑;并创新区域-场地双尺度有限元耦合界面元法,成功实现了三维复杂地质环境条件下地层形变特征及地裂缝生成和扩展的力学机制模拟,为地面沉降、地裂缝易发区精准圈定与防控提供了解决路径;通过总结基于技术创新支撑政府实施的地下水限采、禁采等地面沉降防控实践及其成效,为中国其他省/市地面沉降防控与地下水资源管理起到示范作用。

利用遗传算法实现低倾角卫星星座优化设计

针对热点区域的多重覆盖问题,采用回归圆轨道的共星下点轨迹星座方案,提出基于遗传算法求解单颗卫星轨道参数、利用简单解析公式求解星座轨道参数的方法。首先,建立了回归轨道热点区域多重覆盖模型;其次,以卫星一个回归周期内覆盖时间最长为性能指标,首颗卫星轨道根数利用遗传算法可优化求取;最后,根据星下点轨迹重合这一约束条件设计星座构型,并利用各卫星间几何关系求解各卫星的轨道根数。理论分析和仿真结果表明,该方法简单且易于实现,设计结果正确,可实现回归周期内同一卫星星下点轨迹多次覆盖目标,星座使用卫星少、覆盖频率高,具有较好的工程应用价值。

Genetic diversity and matrilineal structure in Chinese tree shrews inhabiting Kunming,China

Due to their special phylogenetic position in the Euarchontoglires and close affinity to primates,tree shrews have been proposed as an alternative experimental animal to primates in biomedical research.However,the population genetic structure of tree shrews has largely remained unknown and this has hindered the development of tree shrew breeding and selection.Here we sampled 80 Chinese tree shrews（Tupaia belangeri chinensis） in Kunming,China,and analyzed partial mtDNA control region sequence variation.Based on our samples and two published sequences from northern tree shrews（T.belangeri）,we identified 29 substitutions in the mtDNA control region fragment（～ 604 bp） across 82 individuals and defined 13 haplotypes.Seventeen samples were selected for sequencing of the cytochrome b（Cyt b;1134 bp） gene based on control region sequence variation and were analyzed in combination with 34 published sequences to solidify the phylogenetic pattern obtained from control region data.Overall,tree shrews from Kunming have high genetic diversity and present a remarkable long genetic distance to the two reported northern tree shrews outside China.Our results provide some caution when using tree shrews to establish animal models because of this apparent genetic difference.In addition,the high genetic diversity of Chinese tree shrews inhabiting Kunming suggests that systematic genetic investigations should be conducted before establishing an inbred strain for medical and biological research.

EVOLUTIONARY FUZZY GUIDANCE LAW WITH SELF-ADAPTIVE REGION

Effective guidance is one of the most important tasks to the performance of air-to-air missile. The fuzzy logic controller is able to perform effectively even in situations where the information about the plant is inaccurate and the operating conditions are uncertain. Based on the proportional navigation, the fuzzy logic and the genetic algorithm are combined to develop an evolutionary fuzzy navigation law with self-adapt region for the air-to-air missile guidance. The line of sight (LOS) rate and the closing speed between the missile and the target are inputs of the fuzzy controller. The output of the fuzzy controller is the commanded acceleration. Then a nonlinear function based on the conventional fuzzy logic control is imported to change the region. This nonlinear function can be changed with the input variables. So the dynamic change of the fuzzy variable region is achieved. The guidance law is optimized by the genetic algorithm. Simulation results of air-to-air missile attack using MATLAB show that the method needs less acceleration and shorter flying time, and its realization is simple.[KH*3/4D]

西南麦区骨干亲本川麦42重要基因组区段的确定及其对衍生品种的遗传贡献

【目的】川麦42是利用人工合成六倍体小麦选育出的高产、广适的优异小麦品种,是西南麦区重要的骨干亲本,本研究通过明确川麦42重要基因组区段及其对衍生品种的遗传贡献,为西南麦区突破性品种培育提供分子设计依据。【方法】利用170个SSR和2268个DArT标记分析川麦42遗传组分在7个衍生品种中的分布与传递情况;根据已构建的遗传图谱和定位到的产量性状QTL,明确川麦42遗传组分对各个衍生品种的遗传贡献。【结果】川麦42遗传组分在7个一代衍生品种中分布与传递频率不同,其中川麦56、川麦58、川麦64、川麦104、川麦90和川麦91继承了50%以上的川麦42的遗传组分,平均为64%,高于理论值,而川麦92则低于25%。17条小麦染色体上的92个等位位点在川麦42衍生品种中具有较高的分布频率,得到稳定传递;对比已构建的川麦42遗传连锁图谱及其定位到的QTLs,发现位于2A、2B、4A、4D、5B、5D、5A、6D、7A和7D染色体上11个基因组区段与重要农艺性状QTL紧密连锁,其中4A、4D、5B、5D和7D染色体上川麦42单倍型可提高衍生品种的穗粒数、千粒重和小区产量;位于5B染色体Xgwm234~Xgwm371区段携带千粒重QTL,川麦42单倍型最高可增加千粒重2.21 g;位于4D、5D和7D染色体区段携带小区产量QTL,川麦42单倍型最高增产率分别为8.92%、6.33%、4.79%。【结论】携带产量性状增效QTL并且在衍生品种中能够高频传递的基因组区段是川麦42能够成为西南麦区骨干亲本的重要遗传基础,川麦42重要基因组区段的确定为西南麦区小麦骨干亲本选择及突破性品种的培育提供了重要的理论参考。

应用STR荧光标记分析烟台地区草莓种质资源遗传多样性

本研究以烟台地区1份野生草莓种质和6份常规栽培品种为试材,选取已发表具有扩增多态性的11对STR荧光标记引物进行扩增,采用多重荧光毛细管电泳检测,分析了该地区草莓种质的遗传多样性,并构建了其分子身份证.结果表明,用这11对引物从7份草莓种质中共检测到60个STR等位基因位点,平均每对引物5.45个,扩增片段长度在90~270 bp之间,多态信息含量平均为0.676,可用于草莓种质的多态性检测.聚类分析显示7份草莓种质间的遗传相似系数为0.077~0.842,在遗传相似系数为0.257时,7份种质被分为3个类群,W1(野生草莓)与S2(丰香种质)同源性较高.对7份草莓种质进行不同等位基因编码,构建了分子身份证.本研究结果可为烟台地区草莓种质资源鉴定、保护和开发利用提供重要依据.

塔北地区碳酸盐岩地层超压形成机制研究

塔北地区古生界碳酸盐岩地层异常压力普遍发育,地层存在多套压力系统。为提高塔北地区碳酸盐岩地层压力预测的精度,研究了该地区地层异常压力的成因。通过对塔北地区实测压力、测井曲线、声波速度—密度交会图、声波速度—垂向有效应力交会图、气测数据及地震资料的综合分析,表明深层碳酸盐岩地层纵向上发育常压、弱超压和超压系统。弱超压系统压力系数普遍大于1.10,部分超压点压力系数大于1.50,超压主控因素为构造挤压作用和生烃作用。选取引入超压成因机制的Bowers法对深层碳酸盐岩地层压力进行预测,与实测数据相对比,该方法预测的地层压力相对误差低于5.000%,预测精度较高,满足现场工程需求,对塔北及相似地区深层、超深层碳酸盐岩超压成因及压力预测研究具有指导意义。

庆阳驴mtDNA D-loop区遗传多样性及起源分析

[目的]研究庆阳驴养殖群体的遗传多样性与母系起源,了解其遗传信息,为保护庆阳驴种质资源、选育和遗传改良工作提供理论依据。[方法]随机选取133头庆阳驴,对其线粒体DNA(mitochondrial DNA,mtDNA)D-loop区序列进行PCR扩增、测序及比对,并探讨庆阳驴的遗传多样性与母系起源。[结果]在获得的520 bp D-loop碱基序列中,AT含量(57.3%)高于GC含量(42.8%),表现出碱基的偏倚性;检测到38个变异位点,包含8个碱基对的转换;其核苷酸多样性(Pi)、单倍型多样性(Hd)、平均核苷酸差异(K)分别为0.01591、0.895和8.274,与欧洲家驴和中国家驴研究的平均值相比较低,说明该驴品种核苷酸变异较为贫乏。庆阳驴mtDNA D-loop区存在35个单倍型,单倍型之间的遗传距离为0.002~0.042。系统进化结果显示,庆阳驴存在2个线粒体支系,表明其具有2个母系起源,且遗传距离表明,庆阳驴与克罗地亚家驴之间的遗传距离较近。[结论]本研究从分子水平初步揭示庆阳驴核苷酸变异比较贫乏,杂交程度高,mtDNA遗传多态性正逐步丧失,应加强庆阳驴品种的遗传资源保护工作。

广西地区中华圆田螺不同地理种群遗传多样性分析

为探究珠江流域广西境内中华圆田螺(Cipangopaludina cathayensis)种群的遗传多样性特征,本研究采用12对微卫星引物对广西地区中华圆田螺10个地理种群的遗传多样性和遗传分化进行分析。结果显示:12个微卫星位点共检测到140个等位基因,多态信息含量(PIC)为0.373-0.923,其中有9个为高度多态性位点,有3个为中度多态性位点。10个地理种群的香农信息指数(I)为0.415-1.226,观测杂合度(Ho)为0.231-0.540,期望杂合度(He)为0.239-0.608,说明这些种群具有较高的遗传多样性。分子方差分析(AMOVA)结果显示,种群内的遗传变异占75%,种群间的遗传变异占25%,遗传分化指数(Fst)为0.248,种群间的遗传分化程度较高。基因流(Nm)为0.391-21.807,除河池都安(HCDA)种群和百色那坡(BSNP)种群外,其余8个种群间的基因交流频繁(Nm>1.000)。种群结构分析发现,BSNP种群与玉林陆川(YLLC)种群的遗传距离较远(D=0.047),遗传分化程度较高(Fst=0.277)。聚类分析和主坐标分析(PCoA)结果显示,HCDA种群和BSNP种群单独为一支,表明这两个种群与其他种群亲缘关系较远。Mantel分析发现,地理距离不是影响各种群间遗传距离大小的主要原因。综上,广西地区中华圆田螺种质资源良好,其中HCDA种群和BSNP种群仍保持着较好的野生资源,具有潜在的开发利用价值。

新疆和田地区鹅细小病毒感染调查及VP1基因遗传进化分析

为了解新疆和田地区鹅细小病毒(Goose parvovirus,GPV)的感染情况及遗传进化特征,试验采集新疆和田地区和田县、于田县、皮山县鹅养殖场的578只死亡雏鹅的内脏(肝脏、脾脏)及肛拭子样本(和田县344只,于田县67只,皮山县167只),采用PCR方法对鹅细小病毒进行检测,并随机选取2份阳性病料样本对鹅细小病毒VP1基因进行PCR扩增、测序、BLAST比对和遗传进化分析。结果表明:共检测出44份鹅细小病毒阳性样品,总阳性率为7.61%(44/578),其中新疆和田地区和田县鹅细小病毒阳性率为12.50%(43/344),于田县鹅细小病毒阳性率为1.49%(1/67),皮山县未检测到鹅细小病毒。随机选取的2株鹅细小病毒(XJHT-1、XJHT-2株)均为经典鹅细小病毒,与鹅细小病毒各参考毒株VP1基因编码氨基酸序列相似性分别为89.5%~95.8%和92.1%~97.3%,与番鸭细小病毒参考毒株VP1基因编码氨基酸序列相似性分别为76.0%~85.4%和78.5%~88.7%。鹅细小病毒XJHT-1、XJHT-2株与鹅细小病毒DY16株(中国江苏)的相似性最高,分别为95.8%和97.3%,遗传距离最近;XJHT-1株与鹅细小病毒GD株(中国广东)和SD-F30株(中国河北)的相似性较低,分别为89.5%和89.6%;XJHT-2株与鹅细小病毒SHM319株(德国)、GD株(中国广东)和SD-30株(中国河北)的相似性较低,分别为92.1%、92.8%和92.8%。说明和田地区部分鹅场存在鹅细小病毒的感染,但阳性率较低,选取的2株毒株与鹅细小病毒DY16株(中国江苏)的氨基酸序列相似性最高,推测可能由鹅细小病毒DY16株进化而来。

基于线粒体Cyt b基因和D-loop区分析元江鲤和杞麓鲤群体遗传结构

本文利用线粒体Cyt b基因和D-loop区部分序列,分析元江鲤(Cyprinus carpio yuankiang)和杞麓鲤(Cyprinus carpio chilia)群体的遗传结构。结果表明,在两个鲤群体中均获得929 bp的Cyt b基因序列和650 bp的D-Loop区序列。两个群体间平均遗传距离为0.00595(Cyt b)、0.00852(D-loop)。Cyt b基因共检测出元江鲤3种、杞麓鲤15种单倍型,两个群体共享两个单倍型(C-Hap1和C-Hap3);D-loop区序列共检测出元江鲤3种、杞麓鲤6种单倍型,两个群体共享两个单倍型(D-Hap1和D-Hap2)。元江鲤和杞麓鲤群体单倍型多样性(Hd)分别为0.30±0.10(Cyt b)、0.25±0.10(D-loop)和0.89±0.04(Cyt b)、0.73±0.05(D-loop)。元江鲤和杞麓鲤群体核苷酸多样性(π)分别为0.12±0.04(Cyt b)、0.12±0.09(D-loop)和0.77±0.09(Cyt b)、0.87±0.07(D-loop),杞麓鲤遗传多样性水平明显高于元江鲤群体。分子方差分析(AMOVA)显示,两个群体间有明显的遗传分化,且遗传变异主要来源于群体间。系统发育分析显示,元江鲤群体单倍型较少,类型较单一,与杞麓鲤群体差异大,多数元江鲤样本单倍型属于华南鲤(Cyprinus carpio rubrofuscus)类型;多数杞麓鲤样本具特有单倍型,部分属于华南鲤、远东鲤(Cyprinus carpio haematopterus)类型。结果表明,杞麓鲤与元江鲤群体遗传分化明显,元江鲤线粒体遗传多样性较低。