【作者】 马志刚；

【导师】 蒋思文；

【作者基本信息】 华中农业大学 ， 动物遗传育种与繁殖， 2007， 硕士

【摘要】 繁殖性状是非常重要的经济性状，妊娠期短的母猪可以缩短繁殖周期，加快繁殖频率，提高其生产能力，而且还可以节省妊娠饲料。根据国内外报道的QTL定位结果、猪-人比较图谱以及基因的生理生化功能，分别选取了三个影响妊娠期长短的候选基因HSD11B1（11βhydroxysteroid dehydrogenase-1，11β-羟基类固醇脱氢酶1），PGHS2（prostaglandin H synthase-2，前列腺素H合成酶2）和MyoG（myogenin，肌细胞生成素）。应用比较基因组学、生物信息学等方法分离鉴定了这些基因，并以清平猪、新清平母系（由清平猪与杜洛克猪杂交形成的品系）、长白猪、大白猪、杜洛克猪、中国瘦肉猪新品系DⅣ₁系、DⅣ₂系为材料，研究了这些基因的多态性位点与猪繁殖性状的相关性。具体结果如下：一、HSD11B1基因的遗传效应分析结果：1)获得清平猪，新清平猪，大白猪，杜洛克猪HSD11B1基因部分基因组序列。经比对分析在不同品种猪基因组扩增序列中检测到22个SNPs，在3’端的一处G／A转换的SNP引起了Bsh1236Ⅰ酶切多态性，建立了该位点的PCR-Bsh1236Ⅰ-RFLP基因分型方法。2)在7个不同品种品系中检测了HSD11B1基因Bsh1236Ⅰ-RFLP基因型频率和等位基因频率分布，发现清平猪与新清平猪的B等位基因频率比其他猪种的高，x²检验结果表明等位基因频率在清平猪和其他猪群之间存在显著或极显著差异。3)在清平猪、新清平母猪、长白猪、大白猪、中国瘦肉猪新品系DⅣ₁、DⅣ₂中进行HSD11B1基因Bsh1236Ⅰ-RFLP标记与繁殖性状的关联分析，结果表明该位点在母猪中BB型比AA型的妊娠期要短，并在初产中国瘦肉猪新品系DⅣ₁妊娠期中表现差异显著（P＜0.05），加性效应显著（P＜0.05）。二、MyoG基因的遗传效应分析结果：1)在7个不同品种品系中检测了MyoG基因MspⅠ-RFLP基因型频率和等位基因频率分布，发现在清平猪中只有MM基因型，在杜洛克中NN型占大多数，x²检验结果表明等位基因频率在清平猪和其他猪群之间存在极显著差异。2)在新清平母猪、长白猪、大白猪、杜洛克猪、中国瘦肉猪新品系DⅣ₁、DⅣ₂中进行MyoG基因MspⅠ-RFLP标记与妊娠期性状的关联分析，结果表明该位点在母猪中MM型比NN型的妊娠期要短，并在长白猪经产妊娠期中表现差异极显著（P＜0.01），且加性效应极显著（P＜0.01）。3)在新清平母猪、长白猪、大白猪、杜洛克猪、中国瘦肉猪新品系DⅣ₁、DⅣ₂中进行MyoG基因MspⅠ-RFLP标记与产仔数性状的关联分析，结果表明该位点在母猪中NN型比MM型的产仔数要多，但是在个别群体中表现差异不显著（P＞0.05）。三、PGHS2基因的遗传效应分析结果：1)获得清平猪，新清平猪，大白猪，杜洛克猪PGHS2基因部分基因组序列。经比对分析在不同品种猪基因组扩增序列中发现，在第8外显子存在一个A／G转换，建立了该位点的PCR-SSCP基因分型方法。2)在7个不同品种品系中检测了PGHS2基因型频率和等位基因频率分布，发现清平猪与新清平猪的B等位基因频率比其他猪种的高，x²检验结果表明等位基因频率在新清平猪和一些猪群之间存在显著或极显著差异。3)在清平猪、新清平母猪、长白猪、大白猪和杜洛克猪中进行PGHS2基因SSCP标记与妊娠期性状的关联分析，结果表明该位点在母猪中BB型比AA型的妊娠期要短，并在清平猪经产妊娠期性状中表现差异显著（P＜0.05），加性效应显著（P＜0.05）。更多还原

【Abstract】 The economic efficiency of swine industry is very important. It is influenced by thegestation length deeply. According to QTL mapping results, pig and human comparativemap and physiological or biochemical functions of genes, three candidate genes wereselected: HSD11B1 （11βhydroxysteroid dehydrogenase-1）, PGHS2 （prostaglandin Hsynthase-2）, MyoG （myogenin）. These genes were isolated and identified withcomparative genomics and bioinformatic approaches, etc. Qingping, New Qingping line,Landrace, Large White, Duroc, Chinese lean type new line DⅣV₁, DⅣ₂ were used in thisstudy. The relationship of the polymorphism of the genes and association studies of thegene polymorphism with reproduction traits were investigated. The main results are asfollowing:1. The analysis results of genetic effect of HSD11B1geneThe partial genomic sequence HSD11B1gene of Qingping, New Qingping line, LargeWhite, Duroc pig breeds were obtained. Comparative sequencing of these four breedamplified fragments revealed 22 single nucleotide polymorphisms （SNPs）, an PCR-Bsh1236Ⅰ-RFLP was developed to detect G/A transition.For PCR-Bsh1236Ⅰ-RFLP, The frequency of the B allele in Qingping, New Qingpingline is higher than in others during 7 different breeds and lines. The result of x² showedthat there was significant difference between Qingping and other groups.Qingping, New Qingping line, Landrace, Large White, Chinese lean type new lineDⅣ₁, DⅣ₂ were genotyped for population variation investigation and associationanalysis with gestation length. Results showed that the gestation length of genotype BB isless than genotype AA. There was significant difference between genotype AA and BBwith gestation length of first parity in Chinese lean type new line DⅣ₁ breed （P＜0.05）,the additive effect is significant （P＜0.05）.2. The analysis results of genetic effect of Myo G geneQingping, New Qingping line, Landrace, Large White, Duroc, Chinese lean type newline DⅣ₁, DⅣ₂ were used to study allele frequencies. The Qingping is all genotype MM,but the duroc is almost genotype NN. The result of x² showed that there was significantdifference between Qingping and other groups.New Qingping line, Landrace, Large White, Duroc, Chinese lean type new line DⅣ₁,DⅣ₂ were genotyped for population variation investigation and association analysis with gestation length. Results showed that the gestation length of genotype MM is less thangenotype NN. There was significant difference between genotype AA and BB withgestation length of multiple parity in Landrace （P＜0.01）, the additive effect is significant（P＜0.01）.New Qingping line, Landrace, Large White, Duroc, Chinese lean type new line DⅣ₁,DⅣ₂ were genotyped for population variation investigation and association analysis withlitter size. Results showed that the litter size of genotype MM is less than genotype NN.But there were no significant difference in lines. （P＞0.05）3. The analysis results of genetic effect of PGHS2geneThe partial genomic sequence HSD11B1gene of Qingping, New Qingping line, LargeWhite, Duroc pig breeds were obtained. Comparative sequencing of these four breedamplified fragments revealed there was a single nucleotide polymorphism （SNP） in exon8. an PCR-SSCP was developed to detect A/G transition.For PCR-SSCP, The frequency of the B allele in Qingping, New Qingping line ishigher than in others during 7 different breeds and lines. The result of x² showed thatthere was significant difference between New Qingping and other groups.Qingping, New Qingping line, Landrace, Large White, Duroc were genotyped forpopulation variation investigation and association analysis with gestation length. Resultsshowed that the gestation length of genotype BB is less than genotype AA. There wassignificant difference between genotype AA and BB with gestation length of multipleparity in Qingping breed （P＜0.05）, the additive effect is significant （P＜0.05）.更多还原