夏大豆高产育种主要数量遗传性状的选择研究

选用200个山西早熟大豆品种(系),从8个主要数量遗传性状进行分析研究,结果表明:影响山西省早熟品种产量的性状主要是产量性状和形态性状;早熟高产大豆品种选育,在充分考虑生育日期这个限制因素外,不能过分追求百粒重的大小,要重视单株荚数的选择。

我国鸡基因组研究居国际领先

北京2004年12月9日讯：今天，世界著名科学杂志《自然》以3篇主题科学论文的形式，发表中科院北京基因组研究所关于红原鸡基因组和家鸡基因组多态性研究的重大成果。这是我国科学家以加入“人类基因组计划”为起点，在国际合作框架下参与和主持完成的又一突破性成果。此举进一步巩固了我国在国际基因组科学领域的领先地位。

3D graphical visualization of the genetic architectures underlying complex traits in multiple environments

An approach for generating interactive 3D graphical visualization of the genetic architectures of complex traits in multiple environments is described. 3D graphical visualization is utilized for making improvements on traditional plots in quan- titative trait locus (QTL) mapping analysis. Interactive 3D graphical visualization for abstract expression of QTL, epistasis and their environmental interactions for experimental populations was developed in framework of user-friendly software QTLNetwork (http://ibi.zju.edu.cn/software/qtlnetwork). Novel definition of graphical meta system and computation of virtual coordinates are used to achieve explicit but meaningful visualization. Interactive 3D graphical visualization for QTL analysis provides geneticists and breeders a powerful and easy-to-use tool to analyze and publish their research results.

DTNBP1 Gene Is Associated with Some Symptom Factors of Schizophrenia in Chinese Han Nationality

Objective To study the association of DTNBP1 gene with some symptom factors of schizophrenia.Methods A total of 285 unrelated schizophrenic individuals were recruited from December 2004 to January 2009 for genetic analysis,and their symptom factors were assessed based on the Positive and Negative Syndrome Scale(PANSS).The quantitative trait test was performed by the UNPHASED program(version 3.0.12) to investigate the association between scored positive and negative symptoms and the single nucleotide polymorphisms(SNPs) in DTNBP1 gene.Results The quantitative trait test showed allelic association of rs909706 with the excitement symptom of schizophrenia(P<0.05,adjusted by 10 000 permutations),while the genotype C/G of rs2619539 with a negative symptom,lack of spontaneity and flow of conversation(P<0.05,adjusted by 10 000 permutations).Conclusion DTNBP1 variations are possibly associated with some symptoms of schizophrenia,which could partly explain the relationship between the susceptibility gene DTNBP1 and that disease.

Fine mapping of multiple interacting quantitative trait loci using combined linkage disequilibrium and linkage information

Quantitative trait loci (QTL) and their additive, dominance and epistatic effects play a critical role in complex trait variation. It is often infeasible to detect multiple interacting QTL due to main effects often being confounded by interaction effects. Positioning interacting QTL within a small region is even more difficult. We present a variance component approach nested in an empirical Bayesian method, which simultaneously takes into account additive, dominance and epistatic effects due to multiple interacting QTL. The covariance structure used in the variance component approach is based on combined linkage disequilibrium and linkage (LDL) information. In a simulation study where there are complex epistatic interactions between QTL, it is possible to simultaneously fine map interacting QTL using the proposed approach. The present method combined with LDL information can efficiently detect QTL and their dominance and epistatic effects, making it possible to simultaneously fine map main and epistatic QTL.

Genetic Analysis of Main Plant Type-related Traits in Bitter Gourd(Momordica charantia L.)

In this study,the cultivated bitter gourd inbred line‘Foli 112’and the wild bitter gourd accession THMC170 were used as female(P1)and male(P2)parent,respectively,to obtain 4 generations(P1,P2,F1 and F2)through self-crossing and hybridization.The mixed major gene plus polygene inheritance model of plant quantitative trait was used to perform genetic analysis for 5 plant type-related traits including the number of internode,leaf length,leaf width,stem width and internode length in bitter gourd.Results showed that the inheritance of internode number,leaf length and leaf width was in accordance with E-6 model which involved two pairs of equi-dominant major genes with additive-dominant polygene model;the stem width was controlled by additive-dominance-epistasis polygene inheritance model(C-0 model);the inheritance of internode length involved 2 pairs of equi-additive major genes with additive-dominant polygene model(E-4 model).Meanwhile,the heritability(h2)of stem width and internode number was 20.08%and 39.28%,respectively,indicating that they were vulnerable to environment impacts;leaf length,leaf width and internode length had a higher heritability of 51.50%,52.16%and 64.36%,respectively;the inheritance of leaf length was mainly controlled by major gene(the heritability of major gene was 40.75%),indicating that early-generation selection was better for leaf length,while the inheritance of leaf width and internode length was mainly controlled by mutiple minor genes,indicating that it was better to select these two parameters for late generation.

Genetic overlap between salt and low-temperature tolerance loci at germination stage of soybean

Salt and low temperature were both very important factors for soybean production. It was necessary to improve the salt stress and low-temperature tolerance of soybean. The main purpose of this paper was to map the quantitative trait loci(QTL) related with salt tolerance and low- temperature tolerance at germination stage with backcross introgression lines(BILs),and analyze the genetic overlap between them. There were 22 QTL located with BC2 F4 introgression populations after salt stress,and 15 QTL were mapped after low-temperature stress. Seven overlapping QTLs between salt tolerance and low-temperature tolerance were detected on 6 linkage groups at germination stage. In total,there were 31.81 % of salt tolerance and low-temperature tolerance loci existed genetic overlap.

Genetic Parameters for Yields and Reproductive Traits of Chinese Holstein Cows in Heilongjiang Province

[Objective] This study aimed to estimate the genetic parameters for milk yield, fat percentage, fat yield and age at first freshening of Chinese Holsteins first lactation cows in Heilongjiang under frigid-temperature and temperature zone. [Method] Records of yield and reproduction from 8 868 Chinese Holstein first lacta- tion cows from 21 herds were utilized to evaluate genetic parameters for Hei- Iongjiangs＇ Chinese Holsteins. Restricted maximum likelihood （REML） method was used with an animal model. [Result] The heritabilities were 0.16 to 0.34 for yields and fat percentage, 0.38 for reproduction （age at the first freshening）, which were similar to estimates for temperate areas from similar methods, except for constituent percentage. Also, the estimates of genetic correlation were high between milk yield and fat yield （0.97）, but were low between milk yield and fat percentage （-0.24）, age at the first freshening （-0.29） and generally antagonistic. [Conclusion] Thus, es- timates of genetic parameters in this frigid and frigid-temperate environment did not differ appreciably from those that occur in temperate dairy areas.

Brain expression quantitative trait locus mapping informs genetic studies of psychiatric diseases

Genome-wide association study（GWAS） can be used to identify genes that increase the risk of psychiatric diseases.However,much of the disease heritability is still unexplained,suggesting that there are genes to be discovered.Functional annotation of the genetic variants may increase the power of GWAS to identify disease genes,by providing prior information that can be used in Bayesian analysis or in reducing the number of tests.Expression quantitative trait loci（eQTLs） are genomic loci that regulate gene expression.Genetic mapping of eQTLs can help reveal novel functional effects of thousands of single nucleotide polymorphisms（SNPs）.The present review mainly focused on the current knowledge on brain eQTL mapping,and discussed some major methodological issues and their possible solutions.The frequently ignored problems of batch effects,covariates,and multiple testing were emphasized,since they can lead to false positives and false negatives.The future application of eQTL data in GWAS analysis was also discussed.

Salinity tolerance in barley during germination——homologs and potential genes

Salinity affects more than 6%of the world’s total land area,causing massive losses in crop yield.Salinity inhibits plant growth and development through osmotic and ionic stresses;however,some plants exhibit adaptations through osmotic regulation,exclusion,and translocation of accumulated Na+or Cl-.Currently,there are no practical,economically viable methods for managing salinity,so the best practice is to grow crops with improved tolerance.Germination is the stage in a plant’s life cycle most adversely affected by salinity.Barley,the fourth most important cereal crop in the world,has outstanding salinity tolerance,relative to other cereal crops.Here,we review the genetics of salinity tolerance in barley during germination by summarizing reported quantitative trait loci(QTLs)and functional genes.The homologs of candidate genes for salinity tolerance in Arabidopsis,soybean,maize,wheat,and rice have been blasted and mapped on the barley reference genome.The genetic diversity of three reported functional gene families for salt tolerance during barley germination,namely dehydration-responsive element-binding(DREB)protein,somatic embryogenesis receptor-like kinase and aquaporin genes,is discussed.While all three gene families show great diversity in most plant species,the DREB gene family is more diverse in barley than in wheat and rice.Further to this review,a convenient method for screening for salinity tolerance at germination is needed,and the mechanisms of action of the genes involved in salt tolerance need to be identified,validated,and transferred to commercial cultivars for field production in saline soil.