猪产仔数性状基因效应与有效因数的研究

利用太湖猪（Ｐ１）、长白猪（Ｐ２）、杂交一代（Ｆ１）、杂交二代（Ｆ２）、杂交三代（Ｆ２）和回交一代（Ｂ２）等６个世代产仔数的材料,分析了猪产仔性状的基因效应和基因数,结果表明上位效应不显著,猪产仔数性状符合加性－显性遗传模式,受一个有效基因控制。太湖猪产仔数性状基因加性值比长白猪高１．３９头,太湖猪高产仔在因对长白猪等位基因呈显性,显性度为０．８１。     

IGF-1基因对长白×蓝塘猪资源群生产性能的遗传效应分析

利用F2代设计建立了由216头F2代个体组成的长白×蓝塘猪资源群,应用PCR-RFLP方法检测F2代个体IGF-1基因的多态性;通过固定模型方法估计了IGF-1不同基因型的最小二乘均值,同时采用混合模型方法分析不同性状IGF-1基因型的遗传效应,并由此计算IGF-1基因的加性和显性效应.固定模型和混合模型方法的分析结果都表明,IGF-1不同基因型对猪断奶后日增重有显著影响,AA型的遗传效应显著比AB型高20.58 g(P=0.0347),IGF-1基因对该性状的加性和显性效应分别为1.78 g和-18.81 g;对胴体组成性状也有影响,AA型和AB型对骨率的遗传效应分别极显著低于BB型5.22%(P= 0.0008)和5.19%(P=0.0007),IGF-1基因对该性状的加性和显性效应分别为-2.61%和-2.58%;AA型胴体瘦肉量的遗传效应显著比AB型少0.45 kg(P=0.0264),IGF-1基因对该性状的加性和显效应分别为0.16 kg和0.61 kg;AA型和AB型皮脂率的遗传效应比BB型分别高8.81%(P=0.0206)和7.64%(P=0.0431),对该性状的加性和显性效应分别为4.41%和3.24%.因此,IGF-1基因的遗传效应分析说明该基因对断奶后日增重、骨率、胴体瘦肉量和皮脂率等4个性状有显著的遗传影响;而加性和显性效应估计值的大小表明,IGF-1基因的遗传效应只有在皮脂率性状上加性效应相对显性效应比较高,可以作为主基因对该性状进行有效选择.     

猪生长激素基因在金鱼中的整合、表达与生物活性(英文)

自Ｐａｌｍｉｔｅｒ于１９８２年首次将大鼠生长激素基因导入小鼠受精卵,培育出“超级鼠”以来,转基因动物技术获得迅速发展。本文以低等脊锥动物为实验动物,探讨猪生长激素基因导入金鱼受精卵后的整合与表达、生物学效应及后代遗传等问题,为进一步研究外源基因在高等脊椎动物（包括猪）内整合与表达的调控机理提供方法上的参考。实验结果表明：采用显微注射方法,将羊金属硫蛋白基因启动子与猪生长激素基因重组的线型ＤＮＡ（Ｆｉｇ．１）片段导入金鱼受精卵中,获得成活实验鱼,经斑点（Ｆｉｇ．２）,Ｓｏｕｔｈｅｒｎ杂交（Ｆｉｇ．３）,筛选ＰＧＨ阳性的转基因鱼作为亲本交配,分别得到Ｆ１代和Ｆ２代。经斑点、ＰＣＲ－Ｓｏｕｔｈｅｒｎ分析（Ｆｉｇｓ．４,５＆６）及放射免疫检测（Ｔａｂ．１）,表明外源基因在部分受体鱼中得到整合和表达,并能通过有性繁殖传递给后代,且仍具生长效应（Ｆｉｇ．７;Ｔａｂ．２）。本实验获得的转基因阳性金鱼数量有限,且只传了两代,似乎不足以说明转基因金鱼后代表观特征的遗传稳定,但转基因金鱼Ｆ１代中存在外源基因整合位点纯合的个体是可能的。这为建立转基因动物纯系奠定了基础。     

玉米籽粒性状的遗传模型研究

用１０个遗传上和籽粒形态性状上具有差异的玉米自交系,依多种可能的交配方法获得亲本Ｐ１、Ｐ２、Ｆ１（Ｐ１× Ｐ２）、Ｆ２、Ｂ１（Ｆ１×Ｐ１）、Ｂ２（Ｆ１× Ｐ２）及其相应反交ＲＦ１、ＲＦ２、ＲＢ１、ＲＢ２共１０个种子世代。种植２年。依广义遗传模型建立包括种子胚乳加性、胚乳显性、母体加性、母体显性和细胞质效应的遗传模型,运用种子数量性状的精细鉴别法［１］和混合模型分析法［２,３］,对粒长、粒宽、粒长宽比、粒厚及百粒重作了性状表达遗传机制的鉴别与探讨。单个组合的遗传模型精细测验表明,５个籽粒性状的遗传主要受母体显性和胚乳基因型（包括加性和灵性）的控制,一个组合的粒宽、粒厚和百粒重上还检测到细胞质效应。对２５对 Ｆ１正反交组合世代均值依ＭＩＮＱＵＥ法分析的结果表明,５个籽粒性状的遗传方差中,母体遗传方差占６０％以上,胚乳基因型方差低于４０％,粒长和百粒重还有细胞质效应,约占１０％～３０％。可见,籽粒性状的遗传特点是受多套遗传系统控制,其中以母体基因型的作用最大。     

长白猪和太湖猪不同生长阶段脂肪中肉质和胴体性状相关基因的表达谱分析

动物个体的皮下脂肪厚度（subcutaneous fat thickness,SFT）和肌内脂肪（intramuscular fat,IMF）含量取决于活体内脂肪酸合成与氧化竞争的动态平衡点．利用包含140个与猪脂肪沉积、代谢和肌肉生长密切相关基因的Oligo功能分类基因芯片检测了脂肪型的太湖猪和瘦肉型的长白猪在1,2,3,4和5月龄间背部皮下脂肪中这些基因的动态表达变化,发现长白猪有25个基因在月龄间的表达差异达显著水平（P〈0．05）,且包含23个基因的“参与脂肪或类固醇代谢的酶和调节蛋白”基因分组在品种间具有极显著意义（P〈0．01）．提示两猪种脂肪沉积能力的巨大表型差异可能与这些基因的差异表达规律密切相关．STEM聚类分析显示长白猪和太湖猪各有两个表达模式分别具有极显著（P〈0．01）和显著性意义（P〈0．05）,但太湖猪基因表达谱比较分散,占主导优势的表达模式没有长白猪明显．提示太湖猪脂肪细胞内参与相关代谢活动的基因间的调控关系较长白猪复杂．基于动态贝叶斯模型构建的基因调控网络从一定程度上反映了两猪种在脂肪沉积代谢相关生理生化活动方面存在的明显差异,可从中挖掘相关性状潜在的关键特征基因．此外,对5个差异表达基因的荧光定量RT-PCR验证显示两种实验方法结果的相关系数平均高达0．874±0．071．以上结果筛选出了对于猪脂肪相关性状可能具有重要影响并值得深入研究的一些基因,初步揭示了生长发育过程中脂肪细胞基因表达调控的分子互作机制．     

猪整合素β1基因CRS-PCR多态性与产仔数的关联性分析

文章采用CRS-RFLP技术对长白猪、大白猪和杜洛克猪3个品种的整合素β1基因第5外显子T32207C位点及第7外显子A35230G位点进行单核苷酸多态性分析,并将基因多态性与猪的产仔数进行关联分析。结果表明:32207多态位点的基因型效应对3个品种的总产仔数(TNB)和产活仔数(NBA)影响均不显著;35230多态位点的基因型效应对大白猪和长白猪头胎、二胎及所有胎次的TNB和NBA的影响达到显著(P<0.05)或者极显著水平(P<0.01),基因型GG、AG与AA对产仔数的影响存在差异,其效应为GG,AG>AA。可见整合素β1基因35230位点的G等位基因对大白猪和长白猪的产仔数性状有显著影响。     

利用杂种F2世代鉴定数量性状主基因——多基因混合遗传模型并估计其遗…

大量实验数据和ＱＴＬ作图结果表明：控制数量性状的基因中既有遗传效应较大的主基因,又有遗传效应较小的多基因,其分离世代表现出多峰性,即出现多个分布混合的特征。本文利用混合模型理论的ＡＩＣ信息准则在Ｆ２世代中鉴定影响数量性状的主基因的存在,当主基因存在时通过分离分析估计主基因的遗传效庆以及主基因的遗传变异占总变异的分量;同时还提出利用Ｐ１、Ｐ２、Ｆ１和Ｆ２４个世代鉴定多基因存在的方法。以大豆开花期性状     

我国棉花细胞质雄性不育系育性恢复的遗传基础：Ⅱ.恢复基因与育性增…

以引自美国的哈克尼西棉细胞质雄性不育系ＤＥＳ－ＨＡＭＳ２７７及其恢复系ＤＥＳ－ＨＡＭＦ２７７为对照,对我国５个棉花细胞质雄性不育系进行了育性恢复的遗传学研究。研究结果：５个不育系的育性恢复受两个独立的显性基因控制,Ｒｆ１和Ｒｆ２称为恢复基因,其中Ｒｆ１为完全显性,Ｒｆ２为部分显性,Ｒｆ１对育性恢复的遗传效应大于Ｒｆ２。育性恢复还可被一个称为育性增强基因（Ｅ）的基因所促进,Ｅ基因与Ｒｆ１和Ｒｆ２基因     

水稻单株有效穗数主基因＋多基因混合遗传分析

选择单株有效穗数差异大的3个亲本CB1（15.3）、CB4（6.4）和CB7（11.8）,配制CB1×CB4和CB7×CB4组合,建立了相应的P_1、F_1、P_2、B_1、B_2、F_2群体,将其分为中、晚两个生产季节种植,考察了有效穗数性状.利用主基因＋多基因混合遗传模型理论的Akaike信息准则（AIC）在B_1、B_2、F_2代中鉴定影响数量性状的主基因存在与否,主基因存在时通过分离分析估计主基因和微效基因的遗传效应及所占总变异的分量.结果表明该性状在所有B_1、B_2、F_2中均符合2对加性-显性-上位性主基因＋加性-显性-上位性多基因的遗传模式,主基因遗传率为30.64%-72.26%,多基因遗传率为3.41%-28.20%,总基因遗传率为45.96%-87.29%;相同组合种植季别主基因遗传率及一阶参数对比表明,杂交亲本的选择及种植季别对该性状遗传率影响较小,h_a、h_b、j_（ab）、j_（ba）值均为负值表明显性效应和加性显性互作对该性状表达具有抑制作用.     

抗黄矮病小麦新品系YW443的分子细胞遗传学鉴定

以小麦－中间偃麦草二体附加系Ｌ１衍生抗病系ＰＰ９－１为抗源,与小麦推广品种陕７８５９．丰抗８号杂交并自交,在Ｆ６代中选到农艺性状优良的高抗黄矮病小麦新品系ＹＷ４４３。对ＹＷ４４３及其亲本进行抗病性鉴定。结果表明：ＹＷ４４３高抗大麦黄矮病毒ＧＰＶ、ＧＡＶ株系。利用基因组原位杂交,ＲＦＬＰ分析和ＲＡＰＤ分析,研究诉遗传构成及其抗病基因染色体归属。结果表明：ＹＷ４４３（２ｎ＝４３）的遗传构成了４０条（２     

雌激素受体基因和长白猪繁殖性能相关研究

通过检测612头长白母猪共2 239窝ESR基因的PvuⅡ酶切多态性,分析了不同ESR基因型和长白母猪繁殖性状的相关,以确定ESR基因在猪育种应用的可能性.头胎母猪、第2胎母猪和3胎以上母猪的资料分开统计.群体中B等位基因的频率很低,但似然比检验结果显示群体的基因频率处于哈代-温伯格连锁平衡状态.第1胎BB基因型母猪的总产仔数显著高于AA型母猪(12.05±0.82 vs 10.19±0.24)(P＜0.05),但BB基因型母猪的初生仔猪重显著低于AA型母猪(1.23±0.07vs 1.42±0.02)(P＜0.05).第3胎以上资料合并,BB基因型母猪的总产仔数显著多于AA和AB基因型母猪(11.98±0.63 vs10.90±0.48/10.92±0.51)(P＜0.05),产活仔数显著高于AA型母猪(10.31±0.58 vs 9.43±0.45)(P＜0.05);AB基因型母猪初生仔猪重显著低于AA型母猪(1.44±0.04 vs 1.48±0.04)(P＜0.05).所有资料合并,BB基因型母猪的总产仔数极显著高于AB型母猪(11.63±0.52 VS 10.63±0.42)(P＜0.01),显著高于AA型母猪(11.63±0.52 vs 10.70±0.40)(P＜0.05);BB基因型母猪的产活仔数显著高于AB和AA基因型母猪(10.15±0.50 vs 9.33±0.39/9.41±0.41)(P＜0.05).其余情况下各基因型母猪间繁殖性状间差异不显著(P＞0.05).总之,BB基因型母猪的总产仔数和产活仔数优于其他基因型母猪,但仔猪初生重较低.ESR基因可以作为遗传标记,用于本群长白猪产仔数的选择.     

Molecular Cloning of Porcine SUN5 Gene and Association between a SNP with Litter Size Trait

SUN domain-containing protein 5 (SUN5) is an important reproduction related gene. In this study, we cloned the full-length coding sequence of porcine SUN5 gene through RT-PCR. Sequence analysis of this gene revealed that the pig SUN5 gene encodes a protein of 383?amino acids that has high homology with the SUN5 protein of eight species: wild Bactrian camel (95%), alpaca (95%), Yangtze River dolphin (94%), sperm whale (94%), sheep (93%), black flying fox (93%), goat (92%), and horse (91%). This gene is structured into 13 exons and 12 introns as revealed by computer-assisted analysis. The prediction of transmembrane helices showed that pig SUN5 protein might be a transmembrane protein. PCR-Taq I-RFLP was established to detect the GU475008:c.138 G>A substitution of porcine SUN5 gene coding sequence and eight pig breeds displayed obvious genotype and allele frequency differences at this mutation locus. Association of this SNP with litter size traits was assessed in Large White (n?=?200) and Landrace (n?=?200) pig populations, and the results demonstrated that this polymorphic locus was significantly associated with the litter size of all parities in Large White and Landrace sows (P?相似文献   

Molecular Characterization,Polymorphism, and Association of Porcine GADD45G Gene

Growth arrest and DNA-damage-inducible gamma (GADD45G) is a reproduction related gene. In this study, the full-length cDNA sequence of porcine GADD45G gene was cloned through rapid amplification of cDNA ends (RACE) method. The porcine GADD45G gene encodes a protein of 159 amino acids that shares high homology with the GADD45G of nine species: chimpanzee (97%), sumatran orangutan (97%), white-tufted-ear marmoset (97%), northern white-cheeked gibbon (97%), cattle (97%), human (97%), rhesus monkey (97%), rat (96%), and mouse (95%). This novel porcine gene was assigned to GeneID: 100152997. Phylogenetic analysis revealed that the porcine GADD45G gene has a closer genetic relationship with the GADD45G gene of cattle. Computer-assisted analysis indicated that porcine GADD45G gene is structured in four exons and three introns. PCR-Rsa I-RFLP was established to detect an A/G mutation on the position of 294-bp of coding sequence and eight pig breeds display obvious genotype and allele frequency differences at this mutation locus. Association of this SNP with litter size traits was assessed in Large White (n = 100) and Landrace (n = 100) pig populations, and result demonstrated that this polymorphic locus was significantly associated with the litter size of all parities in Large White and Landrace sows (P < 0.01). Therefore, porcine GADD45G gene could be a useful candidate gene in selection for increasing the litter size. These data serve as a foundation for further insight into this novel porcine gene.     

猪MyoG基因3'端PCR-SSCP遗传多态性及其遗传效应

采用PCR—SSCP方法对长白猪、大白猪、杜洛克猪、山西黑猪和马身猪共636头猪的肌细胞生成素（Myogenin,简称MyoG）基因3’端的遗传多态性进行检测,分析MyoG基因对猪的初生体质量、断奶体质量、6月龄体质量和背膘厚的影响。根据已发表的猪MyoG基因3’端侧翼序列设计3对引物,发现F1／R1引物对扩增的片段有多态性。统计结果发现：长白、大白、杜洛克猪种B基因为优势基因,其基因频率分别为0．8807、0．7256和0．8581：山西黑猪种4基因为优势基因,其基因频率为0．9359;马身猪种只检测到4基因。χ^2独立性检验表明,基因型分布在外来猪种（长白猪、大白猪、杜洛克猪）与地方猪种（山西黑猪、马身猪）间存在极显著差异（P〈0．01）。固定效应模型分析结果表明,初生体质量基因型闻差异显著（P〈0．05）,而断奶体质量、6月龄体质量和背膘厚基因型闻差异不显著（P〉0．05）。最小二乘分析结果表明,BB基因型与其它2种基因型比较有较大的初生质量,同似和AB型比较差异极显著（P〈0．01）。因此,推测MyoG基因对个体的初生体质量存在一足的影响,选择带有B等位基因的个体有望提高个体的初生体质量。     

Study on the Association Between Estrogen Receptor Gene (ESR) and Reproduction Traits in Landrace Pigs

To study the potential use of estrogen receptor gene (ESR) as a genetic marker to improve the reproductive traits of pigs, the genotypes of the ESR PCR product digested by Pvu II were determined in 2 239 litters from 612 Landrace sows. The data of the first, second, and later parities were separately evaluated. Although the frequency of the B allele was much lower than that of the A allele, likelihood ratio test showed that the gene frequencies were in Hardy-Weinberg equilibrium. The effects of ESR of different parities were not equal. In summary, the sows with the BB genotype showed better performance for total number of piglets born (TNB) and number of piglets born alive (NBA), but had a lower average piglet weight at birth (AWB). It was concluded that ESR could be used as a marker for the selection of litter size in the Landrace population.     

A Colon Cancer Related Gene-MLH1, Significantly Affecting the Pig Litter Size

MutL homolog 1, colon cancer, nonpolyposis type 2 (MLH1) is a tumor related gene. In this study, the full-length cDNA sequence of porcine MLH1 gene was cloned through rapid amplification of cDNA ends (RACE) method. The porcine MLH1 gene encodes a protein of 757 amino acids which shares high homology with the MLH1 of five species: chiru (96%), sheep (95%), cattle (93%), southern-white-rhinoceros (92%) and goat (92%). This novel porcine gene was assigned to GeneID: 100337665. Phylogenetic analysis revealed that the porcineMLH1 gene has a closer genetic relationship with theMLH1 gene of southern- white-rhinoceros. PCR-HhaI-RFLP was established to detect GU373696:c.395 G > A substitution of porcine MLH1 gene and eight pig breeds display obvious genotype and allele frequency differences at this mutation locus. Association of this SNP with litter size traits was assessed in Large White (n = 200) and Landrace (n = 200) pig populations, and result demonstrated that this polymorphic locus was significantly associated with the litter size of all parities in Large White and Landrace sows (P < 0.01). Therefore, MLH1 is also a reproduction related gene.     

Litter size and piglet traits of gilts with different prolactin receptor genotypes

Seventy-seven Large White x Meishan F2 crossbred gilts with prolactin receptor (PRLR) genotype AA (n = 26), AB (n = 36) and BB (n = 15) were compared for teat number (FTm), age at first estrus, gestation length (GL), litter size, and litter means of functional teat number (FTp), birthweight (BW), and pre-weaning growth rate (GR). Own placental information was available for 88% of 620 live-born piglets (62 gilts), since placentae were labeled during farrowing. The effect of PRLR genotype of the mother on average placenta weight (PLW) and placenta efficiency (EFF = BW/PLW), was therefore, also analyzed, PRLR genotype significantly (P < 0.05) affected age at first estrus and, as a result (since the gilts were inseminated at a fixed estrus number), age and bodyweight at insemination. Furthermore, PRLR genotype affected total number of piglets born (TNB, P = 0.056) and number of piglets born alive (NBA, P = 0.072), but it did not affect (P > 0.3) GL, BW or GR, neither before nor after correction for litter size. BB gilts were significantly younger at first estrus and younger and lighter at insemination than AA gilts (P < 0.05). AA gilts had larger TNB (P = 0.047) and tended to have a larger NBA (P = 0.062) than BB gilts. TNB was 11.4 +/- 0.7, 10.8 +/- 0.6, and 8.8 +/- 0.9; NBA was 11.1 +/- 0.6, 10.5 +/- 0.6, and 8.7 +/- 0.9; BW was 1309 +/- 40, 1277 +/- 34, and 1290 +/- 53 g; and GL was 113.6 +/- 0.3, 113.8 +/- 0.3, and 113.5 +/- 0.4 days for AA, AB and BB gilts, respectively. The effects on litter size and age at first estrus are independent effects. PRLR affected PLW (P = 0.050) and EFF (P = 0.066), resulting in a difference between AA and BB gilts. PLW was 160 +/- 9, 181 +/- 7 and 196 +/- 11 g and EFF was 7.6 +/- 0.2, 7.3 +/- 0.2 and 6.7 +/- 0.3 for AA (n = 19), AB (n = 29) and BB (n = 14) gilts, respectively. After correction for TNB, the differences disappeared. Functional teat number of the AA. AB and BB gilts was 15.35 +/- 0.22, 15.53 +/- 0.18, and 15.60 +/- 0.29, respectively, and was not affected by PRLR genotype (P = 0.7). Functional teat number of piglets from AA, AB and BB mothers was 14.20 +/- 0.10, 14.37 +/- 0.08, and 14.63 +/- 0.13, respectively. Piglets from BB mothers had on average larger numbers of functional teats compared to piglets from AA mothers (P = 0.028). In conclusion, PRLR gene is a major gene or marker for age at first estrus, litter size, and litter average of number of functional teats in the Large White x Meishan F2 crossbred gilts studied. The favorable allele for litter size (A allele) is the unfavorable allele for age at first estrus and for litter mean of functional teat number.     

Association of EphA4 polymorphism with swine reproductive traits and mRNA expression of EphA4 during embryo implantation

The swine erythropoietin-producing hepatocellular A4 (EphA4) gene, which was detected in the endometrium during embryo implantation in pigs, was one of the potential candidate genes for reproductive traits. In the study, two single nucleotide polymorphism (SNP) loci (EphA4_1 and EphA4_2) in exon 3 of EphA4 gene were analyzed to determine whether EphA4 influenced total number born (TNB) and number born alive (NBA). Association of two diallelic polymorphisms with reproductive traits was assessed in Landrace, Yorkshire and Duroc populations with 2,014 litter records of 765 sows. The results showed that G allele at EphA4_1 locus or C allele at EphA4_2 locus seemed to have advantageous effects on litter size. And the combined analyzed results demonstrated that genotype AGTC, AGCC and GGCC are better than genotype AATT, AATC and AGTT for TNB and NBA in either single parity or all parities. The results in this study demonstrated that EphA4 gene was significantly associated with litter size in pigs. In addition, a high mRNA expression of EphA4 was found in small intestine, large intestine, stomach and endometrium, and the expression decreased during implantation in pigs. Further studies were needed to confirm these preliminary researches.