【作者】 彭志兰；

【导师】 陈宏权； 储明星；

【作者基本信息】 安徽农业大学 ， 动物遗传育种与繁殖， 2007， 硕士

【摘要】 本研究以高繁殖力山羊品种(济宁青山羊)和低繁殖力山羊品种(安哥拉山羊和内蒙古绒山羊)为对象,研究INHBA基因和INHBB基因的单链核苷酸多态性(single nucleotide polymorphisms,SNPs)及其与山羊繁殖力之间的关联性。根据GenBank中发表的牛INHBA基因的外显子1、外显子2和INHBB基因的外显子2序列分别设计4对和2对引物。采用PCR-SSCP技术分别检测济宁青山羊、内蒙古绒山羊和安哥拉山羊在这两个基因座中的SNPs。分析整个山羊群体在多态性基因座上的遗传结构及其与山羊多产性之间的关联。结果表明:1.在6对引物中,有2对引物检测出SNPs;结果显示,INHBA基因(基因座A)外显子2和INHBB基因(基因座B)外显子2分别存在1个SNP位点。2.在基因座A上,其突变位点位于外显子2第583 bp处,检测到一对等位基因A和B。在济宁青山羊和安哥拉山羊中检测到了AA、AB和BB 3种基因型,在内蒙古绒山羊中检测到AB和BB两种基因型。测序分析表明BB型与AA型相比在外显子2的第583 bp处有一个T→C突变,并引起氨基酸改变(脯氨酸→亮氨酸)。济宁青山羊AA、AB和BB基因型频率分别为0.4786、0.4143和0.1071。通过最小二乘均数比较发现,济宁青山羊AA型的产羔数比AB型多0.42只(P＜0.05),比BB型多1.14只(P＜0.01),AB型比BB型多0.72只(P＜0.05)3.在基因座B上,其突变位点位于外显子2第583 bp处,检测到一对等位基因C和D。在济宁青山羊中检测到CC、CD和DD 3种基因型,在内蒙古绒山羊和安哥拉羊中只检测到CD和DD两种基因型。克隆测序发现DD型与CC型相比在外显子2的第840 bp处有A→G突变,并引起氨基酸改变(组氨酸→精氨酸)。济宁青山羊CC、CD和DD基因型频率分别为0.0685、0.500和0.4315。通过最小二乘均数比较发现,济宁青山羊CC型产羔数比CD型多0.73只(P＜0.05),比DD型多0.84只(P＜0.05),CD型比DD型多0.11只(P＞0.05)。4.在2突变位点上,各山羊品种内和品种间存在遗传多态性。济宁青山羊在这2个位点上与其它山羊品种存在较大的遗传差异。可以认为这种遗传变异与山羊的多产性密切相关。可见,INHBA基因和INHBB基因可能是控制山羊高繁殖力性状的主效基因,或与之存在一定程度的连锁。INHBA基因外显子2和INHBB基因外显子2的突变位点可以作为山羊多产性标记辅助选择的候选标记。更多还原

【Abstract】 The purpose of this study was to detect single nucleotide polymorphisms(SNPs) within INHBA gene and INHBB gene,to analyze the genetic structure of three goat breeds,and to investigate the effects of the two genes on litter size of Jining Grey goats. Based on the bovine DNA sequences in GenBank,four and two primer pairs for INHBA gene and INHBB gene,respectively,were designed for PCR.Amplified regions included Exon 1,Exon 2 of INHBA gene.SNPs of INHBA and INHBB from three different goat breeds were detected by single strand configuration polymorphisms (SSCP).The genetic structure of the three populations at polymorphic loci,and the associations of the litter size of Jining Grey does with the two genes were also explored. The results are as follows:1.By 6 pairs of primers,only 2 SNP sites were tested,which located respectively at exon 2 of INHBA(named locus A)and exon 2 of INHBB gene(named locus B).2.At locus A,the mutation site was at 583 bp of the exon 2,which resulted in allele A and B.Sequencing revealed that allele B was caused by T→C mutation.This mutation resulted in proline→leucine(Pro→leu)substitution.Genotypes AA,AB and BB were detected in Jining Grey goats and Angora goats,genotypes AB and BB in Inner Mongolia Cashmere goats.AA,AB and BB genotype frequencies were 0.4786, 0.4143 and 0.1071 respectively in Jining Grey goats.The difference of the kids among the different genotyes In Jining Grey goat,showed that the kids of genotype AA increased 1.14(P＜0.01)than that of genotype BB and 0.42(P＜0.05)than that of genotype AB respectively;the kids with genotype AB increased 0.72(P＜0.05)than with genotype BB.3.At locus B,the mutation site was at 840 bp of the exon 2,which resulted in allele C and D.Sequencing revealed that allele D was caused by A→G mutation.This mutation resulted in His→Arg substitution.Genotype CC,CD and DD were detected in Jining Grey,genotype CD and DD in both Inner Mongolia Cashmere goats and Angora goats.Genotype frequencies of CC,CD and DD were 0.0685,0.5000 and 0.4315 respectively in Jining Grey goats.In Jining Grey goat,the difference of the kids among the different genotyes showed that the kids of genotype CC increased 0.73(P＜0.05) than genotype CD and 0.84 than that of genotype DD respectively,the kids with genotype CD increased 0.11 than with genotype DD(P＞0.05). 4.The genetic polymorphism in 3 breeds at locus A and B was rich.Genetic difference at locus A and B between Jining Grey goat and other two goat breeds was significant,which was associated with the fecundity of goat.Therefore,INHBA gene and INHBB gene may be regarded as major genes for the fecundity of goat,or linked with the major genes influencing the fecundity of goat.It may be feasible to implement the marker assisted selection using the two SNP sites.更多还原