【作者】 孙丽萍；

【导师】 吴登俊；

【作者基本信息】 四川农业大学 ， 动物遗传育种与繁殖， 2007， 硕士

【摘要】 POU1F1(pituitary transcription factor 1)是被鉴定的第一个垂体转录因子，它对哺乳动物的生长发育、新陈代谢起重要的调节作用，具有提高生长速度，降低脂肪沉积等广泛的生物学功能。本实验根据绵羊POU1F1基因第2、3、5外显子和第4内含子序列设计6对引物(P1、P2、P3、P4、P5和P6)扩增LS、ZS、NBG、JDG、JBG和CMG 6个羊群体序列，用PCR-SSCP方法分析其多态性及其与凉山半细毛羊不同月龄体重(初生重、断奶重、断奶日增重、1.5岁体重和2.5岁体重)性状的相关性。所设计的6对引物中，POU1F1基因的第3外显子(P2扩增片段)在所研究的6个群体(LS、ZS、NBG、JDG、JBG和CMG)中均具有多态性，P4和P5扩增片段(内含子4部分序列)只在LS群体中具有多态性，P1、P3和P6扩增片段在所研究的6个群体中都没有发现多态性。P2扩增片段在LS、JDG、JBG和NBG群体中共检测到三种基因型，分别定义为DD、DE和EE，在ZS和CMG群体中只检测到2种基因型(DD和EE)，所选的6个群体均以DD为优势基因型；引物P4扩增片段在LS中也检测到3种基因型，分别定义为AA、AB和AC，其基因型频率分别为0.6082、0.268、0.1237，AA为优势基因型；A、B和c基因的基因频率分别为0.8041、0.1340和0.0619。引物P5扩增片段在LS中只检测到2种基因型，分别为GG和FF，其基因型频率分别为0.9和0.1，GG为优势基因型；G和F基因的基因频率分别为0.9和0.1。群体遗传特性分析结果表明，P2引物扩增片段在LS、JBG和JDG群体中处于低度多态(PIC分别为0.1645，0.2433，0.2442)，而在ZS、CMG和NBG群体中处于中度多态(PIC分别为0.3192，0.3671，0.347)；LS的P4引物扩增片段处于中度多态(PIC为0.303)，P5引物扩增片段处于低度多态(PIC为0.164)。所研究羊群体都具有相对较高的遗传杂合度，说明这些羊还具有一定的选择潜力。凉山半细毛羊体重性状表型资料的相关分析表明，初生重和1.5岁体重(r=0.5408．P＜0.01)断奶重和断奶日增重(r=0.9784，P＜0.01)之间有极显著的正相关。方差分析结果：P2引物扩增片段基因型效应对初生重(P＜0.05)和1.5岁体重(P＜0.01)分别有显著和极显著的影响；P4引物扩增片断的家系效应对初生重(P＜0.05)和1.5岁体重(P＜0.01)分别有显著和极显著的影响；3对有多态性引物的年度效应均对初生重(P＜0.01)、1.5岁体重(P＜0.01)和2.5岁体重(P＜0.01)有极显著的影响。P2引物扩增片段不同基因型与初生重和1.5岁体重的最小二乘差异比较发现，DE基因型对初生重的影响显著高于DD基因型(P＜0.05)，DE基因型对1.5岁体重性状的影响极显著高于DD基因型和EE基因型(P＜0.01)。更多还原

【Abstract】 POU1F1 is the first certified pituitary transcription factor, it plays a role in control ofgrowth process and metabolism, it has far-ranging biological functions in improvinggrowth, reducing fat aggradation and so on. Six primers (P1, P2, P3, P4, P5, P6) weredesigned according exon 2, exon 3, exon 5 and intron 4 of sheep POU1F1 gene.Corresponding sequence of LS, ZS, NBG, JDG, JBG, and CMG popuLations were ampliedby PCR. Polymorphisms of POU1F1 gene were analyzed by PCR-SSCP and alsocorrelative analysis between polymorphisms and weight (BW, WW, WDG, 18W, 30W)traits of LS.In all designed primers, amplified fragment of primer P2(exon 3) have porlymorphismsin all six studied popuLations(LS, ZS, JDG, JBG, CMG, NBG), polymorphisms of primerP4 and P5 fragment only exist in LS sheep population. There were no polymorphisms inprimer P1, P3, P6 PCR fragment in all six studied populations. Primer 2 PCR fragment hasthree genotypes in LS, JDG, JBG and NBG populations, it was defined as EE, DE and EE,genotype DD was dominant in this locus of all six studied popuLations; Primer 4 fragmentalso had three genotypes in LS populations, it was defined as AA, AB, and AC, thefrequencies of genotype AA, AB, AC and allele A, B, C were 0.6082, 0.268, 0.1237/0.8041,0.1340, 0.0619 respectively, genotype AA was dominant; Only two genotypes weredetected in Primer P5 PCR fragment, it was defined as GG, FF, the frequencies of genotypeGG, FF and allele G/F were 0.9, 0.1/0.9, 0.1 respectively, genotype GG was dominant.Results of Genetic characteristics were that there were low polymorphisms on primerP2 fragment in LS, JBG and JDG populations (PIC 0.1645, 0.2433, 0.2442 respectively),midrange polymorphisms exists in ZS, CMG, and NBG populations (PIC 0.3192, 0.3671,0.347 respectively); primer P4 fragment also midrange polymorphisms in LS sheeppopulations (PIC=0.303), primer P5 fragment low polymorphisms in LS sheep populations(PIC=0.164).Results of correlative analysis of phenotype weight traits were that birth weight and18-month weight (r=0.5408, P＜0.01), Weaning weight and Weaning daily gain (r=0.9784, P＜0.01) had great significant difference. Results of variance analysis were thatgenotype had significant difference and great significant difference to birth weight and 18-month weight respectively in primer 2 of LS sheep; family effect had significantdifference and great significant difference to birth weight and 18-month weightrespectively in primer 4; year effect of three polymorphism primers had great significantdifference to birth weight, 18-month weight, and 30-month weight. Comparisons of leastsquare was carried between different genotypes and birth weight, 18-month weight ofprimer 2 PCR fragment, the results were that influence of genotype DE on birth weightsignificant exceeded genotype DD, but genotype DE had great significant difference withgenotype DD and EE in 18-month weight.更多还原