【作者】 田腾飞；

【导师】 李祥龙；

【作者基本信息】 河北农业大学 ， 遗传学， 2012， 硕士

【摘要】 本试验根据GenBank上已发表的绵羊(EU185099)Agouti基因序列进行设计引物,扩增山羊Agouti基因3’UTR区,测序结果表明该片断的长度为190bp。对山羊Agouti基因内含子3测序分析发现四个g.A4756C、g.C4971T、g.A5344G和g.AGG5124-5125变异位点,并对这四个变异位点进行分析。研究发现这4个突变位点共有6种单倍型,分别为ACAA(71.31%)、ATBG(13.11%)、CTBG(7.38%)、ATAA(4.92%)、ATAG(1.64%)、CTAG(0.82%)。在济宁青山羊(青灰色)、辽宁绒山羊(白色)、雷州黑山羊(黑色)山羊中单倍型几乎都为ACAA,但是在南江黄羊快长系(棕褐色)山羊中有不同的单倍型。因此,推测这些突变位点可能在山羊毛色形成过程中发挥一定作用。在山羊Agouti基因内含子3上g.A4756C位点发现了两个等位基因A和C,青灰色(济宁青山羊)、白色(辽宁绒山羊)和黑色(雷州黑山羊)为主的山羊品种中有较高频率的等位基因A。棕色山羊(南江黄羊快长系)A等位基因的频率为54.69%,其三种基因型分布比较平均。分析表明g.A4756C的C等位基因可能与控制山羊棕色表型的位点存在连锁关系,CC基因型为与棕色被毛相关的基因型。在山羊Agouti基因内含子区g.C4971T位点也发现了两个等位基因C和T,济宁青山羊(JN)中C等位基因的频率为98.33%;雷州黑山羊(LH)C等位基因的频率为93.33%,辽宁绒山羊(LR)中C等位基因的频率为100.00%,南江黄羊快长系(NK)中T等位基因的频率为100.00%,全部为TT基因型。分析表明g.C4971T的T等位基因可能与控制山羊棕色表型的位点存在连锁关系,TT基因型为与棕色被毛相关的基因型。在山羊Agouti基因内含子3上g.A5344G位点发现了两个等位基因A和G,其中A等位基因在济宁青山羊、雷州黑山羊和辽宁绒山羊中占优势,等位基因频率分别为:100.00%、96.67%、100.00%,但从基因型上看,济宁青山羊和辽宁绒山羊中全部为AA基因型,雷州黑山羊中AA基因型占绝对优势,只有南江黄羊快长系中有GG基因型并且占绝对优势。分析表明g.A5344G的G等位基因可能与控制山羊棕色表型的位点存在连锁关系,GG基因型为与棕色被毛相关的基因型。在山羊Agouti基因内含子3中g.AGG5124-5125插入位点发现了两个等位基因A(非插入AGG碱基)和B(插入AGG碱基)。其中A等位基因在济宁青山羊、雷州黑山羊和辽宁绒山羊中占优势,等位基因频率分别为:98.33%、90.00%、96.67%,但从基因型上看,济宁青山羊和辽宁绒山羊中全部为AA和AB基因型,雷州黑山羊中三种基因型都有,在这三个山羊品种中AA基因型占绝对优势,在南江黄羊快长系中BB(71.87%)基因型占绝对优势。由此我们推测g.AGG5124-5125插入位点的B等位基因可能与控制山羊棕色表型的位点存在连锁关系,BB基因型为与棕色被毛相关的基因型。经单倍型分析,发现ACAA(71.31%)、ATBG(13.11%)、CTBG(7.38%)、ATAA(4.92%)、ATAG(1.64%)、CTAG(0.82%)六种单倍型。在济宁青山羊(青灰色系)和辽宁绒山羊(白色系)两个品种中,几乎所有个体的单倍型为ACAA,CTBG的单倍型占少数,但是在雷州黑山羊(黑色系)和南江黄羊快长系(棕色系)的品种中有不同的单倍型,推测CTBG的单倍型可能与棕色表型相关。聚类结果表明4个地方山羊品种分为两类,第一类为具有棕色毛色表型位基因的南江黄羊快长系,第二类为具有黑色、灰色以及白色等位基因的济宁青山羊、辽宁绒山羊和雷州黑山羊。经过和毛色相关分析表明,在这4个地方山羊品种中,A4756C、g.C4971T、g.A5344G和g.AGG5124-5125这四个位点的突变和山羊的毛色有显著性的相关。本试验的聚类结果反映了4个不同地方山羊品种在Agouti基因A4756C、g.C4971T、g.A5344G和g.AGG5124-5125的群体间的遗传关系。更多还原

【Abstract】 The primers are designed according to the sheep Agouti gene(EU185099) that has published in GenBank. The sequenced length of 3’UTR region of goat is 190bp. The g.A4756C、g.C4971T、g.A5344G and g.AGG5124-5125 variable sizes are found in the 3rd intron of goat Agouti gene, and then analyse the four variation sites. Research shows that they have six haplotypes that is ACAA(71.31%)、ATBG(13.11%)、CTBG(7.38%)、ATAA(4.92%)、ATAG(1.64%)and CTAG (0.82%) in the four variable sites. Almost all individuals of JN with grey coat color, LH with black coat color and LR with white coat color were haplotype ACAA, but NK with brown coat color had different haplotypes. It is infered that these variable sites may be play a certain role in color goat of the process of forming.A and C alleles of g.A4756C locus were found in the 3rd intron of goat Agouti gene, and the frequency of A allele is high in cinerous, white, and black variey. The frequency of A allele is 54.69% in Brown goats that the distribution of three genotype is hypodispersion. The C allele of g.A4756C may exist chain relation with sites that controlled the brown phenotype of goats, and CC genotype is related with brown hair by the analysis.The C and T allele of g.C4971T locus were found in intron region of Agouti gene. The frequency of C allele is 98.33% in JN, the frequency of C allele is 93.33% in LH, the frequency of C allele is 100% in LR and the NK, which the genotype is all TT. The T allele of g.C4971T may exist chain relation with sites that controlled the brown phenotype of goats, and TT genotype is related with brown hair by the analysis.The A and G allele of g.A5344G locus were found in the 3rd intron of Agouti gene. The A allele was dominated in JN、LH、LR, The genotype was AA in JN and LR, and AA genotype is absolute advantage in LH, on the contrary, the GG genotype was absolute advantage in the NK. The G allele of g.A5344G may exist chain relation with sites that controlled the brown phenotype of goats, and GG genotype is related with brown hair by the analysis.The A and B allele of g.AGG5124-5125 insert locus were found in the 3rd intron of Agouti gene, which the A was not inserted the AGG, but B was inserted by AGG. The A allele was dominated in JN, LH and LR, the frequency of A allele was 98.33%, 90.00% and 96.67% separately. The genotype was AA in JN, the genotype was AB in LR, and three of genotypes were existed in LH, the AA genotype was rich in these three breeds, on the contrary, the BB genotype (71.87%) was absolute advantage in the NK. So we conjectured that the B allele of g.A5344G may exist chain relation with sites that controlled the brown phenotype of goats, and BB genotype is related with brown hair by the analysis. After the single times type analysis,found six single times type that ACAA(71.31%)、ATBG(13.11%)、CTBG(7.38%)、ATAA(4.92%)、ATAG(1.64%)、CTAG(0.82%). Almost the JN and LR is ACAA, the single times type that ACAA is small proportion. But there are different single times type in LH and NK, single times type that CTBG could relate with brown phenotype.The result of cluster shows that the 4 local breeds of goat were divided into two classes, the one is the NK that allele has the brown hair phenotype; the other one is JN, LH and LR, which allele has black, grey and white hair phenotype. The relative analysis shows that the mutations of A4756C、g.C4971T、g.A5344G and g.AGG5124-5125 locus were significantly related with hair of goat in these 4 local breeds. The result of cluster can just reflect the heredity relation of these 4 local breed goat by the A4756C、g.C4971T、g.A5344G and g.AGG5124-5125 locus of Agouti gene, but not real heredity relation. We need to further study in order to the genetic relationship of 4 local goat breeds.更多还原