共查询到20条相似文献，搜索用时 156 毫秒
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水禽的经济性状多为数量性状,数量性状基因座(quantitative trait loci, QTL)是调控数量性状表达的遗传基础,因此QTL的定位是分子育种的基础。全基因组关联分析(genome wide association studies, GWAS)作为鉴定表型与基因型关系的一种分析策略,是挖掘畜禽QTL的重要手段,并已经成功应用于猪、牛、鸡等畜禽的遗传育种工作中。利用GWAS可以定位与水禽经济性状相关的QTL,确定影响水禽性状的功能基因或主效基因,从而实现对水禽重要性状的改良。文章综述了GWAS在水禽重要性状研究上的应用效果,并分析了不足之处,以期为完善水禽遗传育种与遗传改良方法提供参考。 相似文献
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肉鸭经济性状的主基因指数分析 总被引：1，自引：0，他引：1
肉鸭经济性状的主基因指数分析龚炎长，罗清尧，师守坤（中国农业大学动物科技学院北京１０００９４）前言主效基因（Ｍａｊｏｒｇｅｎｅ）是指对数量性状（经济性状）有较大影响的单个基因（相对于微效基因），但这只是一个较为模糊的概述，较为深刻的理解是Ｍｏｒｔｏｎ... 相似文献
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多数家畜的经济性状是数量性状,如羊毛品质、肉质、生长速度、抗病力等.每个性状都是由多个基因调控的,而且这些基因对性状的影响大小是不均衡的,有的是主效基因,有的是辅助基因.微卫星DNA在染色体上是高度随机分布的,如果证实微卫位点专一性地与某主效基因之间是连锁的,那么微卫星标记的位置就可以辅助定位该主效基因.羊具有54条染色体,其中有26对常色体和两条性染色体[1].在1995年,绵羊的G-带核型(G-band karyotype )由北美第九国家动物细胞遗传(9th North American Colloquium on Domestic Animal Cytogenetics)所证实并由其进行了基因定位[1]. 相似文献
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与畜禽经济性状相关的主效基因的研究越来越受到关注。本文就与绵、山羊经济性状相关的主效基因研究进展进行综述,为羊主效基因的进一步研究提供参考。 相似文献
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《动物科学与动物医学》2005,22(5):70-70
随着人们生活水平的提高，对猪肉肉质提出了更高要求。然而肉质是一个相当复杂的数量性状，各肉质性状间存在着复杂的相关，并且对内质的研究需要结合屠宰后的表型数据，这些给肉质的检验和评定带来很大的不便。近年来随着对基因结构和功能研究的不断深入，涌现出DNA水平的遗传分析。人们研究发现肉质性状表型位的变异，除了受微效多基因控制外，还受主基因的作用。对数量性状产生巨大效应的单个基因或位点称为主基因即主效基因，是相对于微效多基因而言的。我们把一些与生产．经济性状(数量性状)密切相关的基因作为候选基因加以研究，这些候选基因对主效基因或与主效基因相连锁基因的确定，标记辅助选择，及从DNA水平上对研究对象进行选择有遗传稳定，准确度高的优点。为此本文把对影响猪肉肉质脂肪性状主要候选基因的研究状况做一论述，为今后培育低脂肪优良猪品种的育种工作奠定基础。 相似文献
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对EPOR、MYPN 2个候选基因进行SNPs检测,并与肉质性状的关联分析,以期为分子育种提供依据.采用PCR-SSCP及PCR-RFLP方法对目的基因片段进行SNPs检测,结果显示,在研究群体内,EPOR基因不存在SNP,而MyPN基因存在2个SNP.用SAS软件对MyPN基因的2个SNP位点与部分肉质、胴体性状进行关联分析,结果表明,在本试验群体中,SNP1对背膘厚、导电性、眼肌面积和肌内脂肪的影响都达到了显著水平(P<0.05);SNP2对其中的背膘厚和肌内脂肪含量影响达到了显著水平(P<0.05);另外性别、品种对部分性状也有较大影响(P<0.05).结合本研究结果和其它相关研究结果,可以推断MYPN基因可能是影响肉质、胴体性状的主效基因或与控制这些性状的主效基因连锁,可以作为肉质、胴体性状的候选基因. 相似文献
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猪的许多重要经济性状都是具有复杂遗传基础的数量性状。长期以来,遗传育种学家们一直渴求了解这些数量性状的遗传机理,识别引起性状变异的基因,从而在分子水平上对这些基因进行操作。近几十年来,大量的理论研究和实验结果表明,真实的数量性状既受到数目较多的微效基因的影响,还受到一个或少数几个起主导作用的主效基因的影响。Geldermann将这些对数量性状的变异有较大影响的单个基因或紧密连锁的基因簇统称为QTLs。QTL的提出从理论上修正了数量性状微效多基因假说,为研究数量性状单基因作用及其互作效应以及建立在此基础上的遗传分析模… 相似文献
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繁殖性状是养猪生产过程中重要的经济性状。如何提高猪的繁殖性状直接影响着养猪业的经济效益。本文综述了猪繁殖性状主基因和QTL,并对影响猪繁殖性状的主基因和QTL研究进展作了阐述。 相似文献
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繁殖性状是养猪生产过程中重要的经济性状.如何提高猪的繁殖性状直接影响着养猪业的经济效益.本文综述了猪繁殖性状主基因和QTL,并对影响猪繁殖性状的主基因和QTL研究进展作了阐述. 相似文献
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利用主要农艺性状上具有显著差异的荻和南荻为亲本,杂交得到种间杂交种F1群体(232个单株)为试验材料,对荻和南荻杂交种茎节数、叶片长、叶宽、主茎长、花茎长、花序长、株高、基部茎径、平均单分蘖干重、最大分蘖干重、分蘖数和单株重等12个主要农艺性状的杂种优势进行了度量,采用主基因+多基因混合遗传模型对F1杂交群体的12个主要农艺性状进行遗传和相关性分析。结果表明,在F1分离群体中12个主要农艺性状呈连续的、单峰、偏态分布,说明这些性状为多基因控制的数量性状。除基部茎径外的其他11个农艺性状都有较大的中亲优势,其中单株重、平均单分蘖干重、花序长、主茎长、株高、最大分蘖干重具有显著的超高亲优势,说明杂种优势可以作为荻和南荻育种的主要方法。混合遗传分析表明,花茎长、最大茎重能检测到1对主基因,叶片宽、主茎长、株高、分蘖数、单茎均重、单株重能检测到2对主基因的存在,主基因遗传率大小顺序为叶片宽(87.76%)>单株重(81.48%)>单茎均重(65.12%)>分蘖数(59.20%)>主茎长(49.87%)>株高(48.01%)>花茎长(47.75%)>分蘖最大茎重(37.19%)。产量相关性状中的单株重、单茎均重和分蘖数具有较高的主基因遗传率,适合于早期世代选择。这12个农艺性状间存在一定的相关性,多数性状间的相关性为极显著的正相关,其中单株重与分蘖数、单茎均重、主茎长和株高的相关系数最大,在育种实践中可以利用相关性状进行间接选择。 相似文献
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Production traits of a Rhode Island Red layer line were analyzed to detect carrier animals with major genes that influenced a particular trait by applying the major gene index (MGI) approach. This method was used to examine the deviation of predicted breeding values between parents and offspring. Advantages of this method include its simplicity and time‐reducing, cost‐saving benefits compared with any other statistical approach for screening major genes. The layer line had been selected based on the desired gain index for 6 years at the National Livestock Breeding Center, Okazaki station. The line consisted of 125 sires and 2986 dams. Two economic traits as breeding objectives were studied – age at sexual maturity (ASM, days) and egg production efficiency (EP, %). The MGI detected nine sires and 23 dams as carriers with major genes for ASM, and five sires and 26 dams for EP. They were identified as important breeding stock, and pedigree information provided candidates possessing major genes with favorable effect at the founding of the selected layer line. It seems likely that the simple approach of the MGI could be a useful preliminary method for detecting carrier animals with major genes before applying molecular techniques on a sampled population to identify in more detail the existence of major genes and their carriers. 相似文献
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用RAPD技术筛选中国荷斯坦牛产奶量性状遗传标记 总被引：10，自引：3，他引：7
选用320条10碱基随机引物在由36头高产（305d产奶量〉8500kg）和32头低产（305d产奶量〈5600kg）中国荷斯坦牛所组成的2个DNA池间进行RAPD-PCR扩增，从中筛选出稳定性好、带型清晰且在2个DNA池间有明显差异的RAPD引物24条。用筛选到的24条引物对所有个体进行PCR检测，得到了5个与奶牛产奶量性状相关的RAPD标记，并对其中4个进行了克隆测序和SCAR标记转化以及生物信息学分析。结果表明：SCAR标记yield—s139与产奶量密切相关，应用电子克隆方法已将该标记由921bp延伸到2141bp，经同源性比较发现，此标记对应于奶牛基因组中LINEs家族中的一个重复元件，推测该元件附近可能存在与产奶量性状相关的QTLs或主效基因。 相似文献
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One of the major determinants for litter size in pigs is prenatal mortality. It occurs most frequently during the first few weeks of gestation and can be attributed to abnormalities in developmental processes during embryogenesis including trophoblastic elongation and blastocyst implantation. Improvement of litter size has been attempted by means of phenotypic selection. However, another promising approach in pursuit of this aim has been the use of genotypic information. Reproductive traits in general are well-suited for application of marker-assisted selection (MAS). The possibility of exerting selection criteria at the molecular level shortens the generation interval as the selection decision can take place early in the life of an animal. Moreover, in consideration of the sex-limited nature of reproductive traits, genotypic information allows for selection in the gender in which the trait cannot be directly observed. Accordingly, there has been considerable interest in mapping and identifying genes involved in the regulation of reproductive traits and in elucidating their expression patterns. This review offers a comprehensive, if not exhaustive, account of the efforts being made and the approaches currently used in this field. One approach has been to choose candidate genes a priori because of the physiological importance of the proteins they encode and their role in the reproduction of other mammals. The usefulness of candidate genes is then examined by association studies between genetic polymorphisms identified in the respective candidate genes and the phenotypic reproductive traits. The other approach discussed uses pre-existing or designed families for linkage analyses in order to map the location of quantitative trait loci (QTL) for the reproductive trait of interest. The results reported were not consistent among different studies but the QTL regions detected may be useful for identification of positional candidate genes in further molecular genetic studies. However, a better understanding of porcine reproduction requires that these functional genomic approaches are merged and integrated with detailed analyses of the proteome to establish linkages between predisposition and physiology. 相似文献
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Markers flanking DNA regions, where quantitative trait loci (QTL) have been previously spotted, can be used to trace the common inheritance of major genes for a better definition of covariances among animals. A practical approach to the use of marker data to refine the additive relationship matrix used in the traditional best linear unbiased prediction (BLUP) methodology is presented. The technique allows the number of the mixed model equations to be kept to an animal level, blending polygenic pedigree data with marker haplotype information. The advantage of this marker-assisted selection (MAS) approach over BLUP selection has been assessed through a stochastic simulation. A finite locus model with 32 independent biallelic loci was generated with normally distributed allelic effects. The heritability of the trait, measured on both sexes and on females only, was set to 0.2 and 0.5. Five-allelic markers 2, 10 and 20 cM apart, bracketed the QTL with the largest effect on the trait, accounting for 17% of the genetic variance. The bracketed QTL had two or eight alleles and its position was undefined within the bracket. Results show a moderate 2% advantage of MAS over BLUP in terms of higher genetic response when trait was recorded on both sexes and heritability was 0.2. The benefit is in the short term, but it lasts longer with polyallelic QTL. When the trait was recorded on females only, MAS produced only a small and insignificant genetic gain, but reduced the overall inbreeding in the population. MAS was also inefficient when heritability was 0.5. 相似文献
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Jiuxiu Ji Guorong Yan Dong Chen Shijun Xiao Jun Gao Zhiyan Zhang 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(3):217-228
The average daily gain (ADG) and body weight (BW) are very important traits for breeding programs and for the meat production industry, which have attracted many researchers to delineate the genetic architecture behind these traits. In the present study, single‐ and multi‐trait genome‐wide association studies (GWAS) were performed between imputed whole‐genome sequence data and the traits of the ADG and BW at different stages in a large‐scale White Duroc × Erhualian F2 population. A bioinformatics annotation analysis was used to assist in the identification of candidate genes that are associated with these traits. Five and seven genome‐wide significant quantitative trait loci (QTLs) were identified by single‐ and multi‐trait GWAS, respectively. Furthermore, more than 40 genome‐wide suggestive loci were detected. On the basis of the whole‐genome sequence association study and the bioinformatics analysis, NDUFAF6, TNS1 and HMGA1 stood out as the strongest candidate genes. The presented single‐ and multi‐trait GWAS analysis using imputed whole‐genome sequence data identified several novel QTLs for pig growth‐related traits. Integrating the GWAS with bioinformatics analysis can facilitate the more accurate identification of candidate genes. Higher imputation accuracy, time‐saving algorithms, improved models and comprehensive databases will accelerate the identification of causal genes or mutations, which will contribute to genomic selection and pig breeding in the future. 相似文献