FSHβ基因PCR-SSCP多态性及其与济宁青山羊高繁殖力关系的研究

PCR-SSCP Polymorphism of FSHβ Gene and Its Relationship with Prolificacy of Jining Grey Goats

采用PCR-SSCP技术检测促卵泡素β亚基(follicle-stimulatinghormoneβ,FSHβ)基因5′调控区、外显子1和外显子2在高繁殖力山羊品种(济宁青山羊)和低繁殖力山羊品种(辽宁绒山羊、波尔山羊、安哥拉山羊)中的单核苷酸多态性,同时研究该基因对济宁青山羊高繁殖力的影响。结果表明:山羊与绵羊的FSH基因该段核苷酸序列同源性为98%。9对引物中,只有P9的扩增片段存在多态性。P9的扩增片段在济宁青山羊和辽宁绒山羊中检测到AA、AB和AC3种基因型;在波尔山羊中检测到AA、CC和AC3种基因型;在安哥拉山羊中检测到AA、BB、CC、AB、AC和BC共6种基因型。测序分析发现BB型与AA型相比在外显子2的第94bp处有G→A突变,并引起氨基酸改变(丙氨酸→苏氨酸);CC型与AA型相比在外显子2的第174bp有一处C→T沉默突变。济宁青山羊AA、AB和AC基因型频率分别为0.686、0.137和0.177。AA基因型济宁青山羊产羔数最小二乘均值比AB基因型的多0.78只(P<0.05),比AC基因型的多0.64只(P<0.05)。

The follicle-stimulating hormone beta-subunit （FSHβgene was studied as a candidate gene for the prolificacy in Jining Grey goats. According to the sequence of ovine FSHβ gene, nine pairs of primers were designed to detect single nucleotide polymorphisms of 5＇ regulatory region, exon 1 and exon 2 of FSHβ gone in both high fecundity breed （Jining Grey goat） and low fecundity breeds （Liaoning Cashmere goat, Boer goat and Angora goat） by PCR-SSCP. The results indicated that the homology of nucleotide sequence of this fragment between goat and sheep was 98 percent. Only the products amplified by primer P9 displayed polymorphism. Three genotypes （AA, AB and AC） were detected in Jining Grey goats and Liaoning Cashmere goats. Three genotypes （AA, CC and AC） were detected in Boer goats. Six genotypes （AA, BB, CC, AB, AC and BC） were detected in Angora goats. Sequencing revealed a G→A mutation at 94 bp of exon 2 of FSHβgene in the BB genotype in comparison to the AA genotype and a C→T mutation at 174 bp of exon 2 of FSHβ gene in the CC genotype in comparison to the AA genotype. The former mutation resulted in an amino acid change： alanine→threonine, and the latter mutation did not cause any amino acid change. Genotype frequency of AA, AB and AC was 0.686, 0.137 and 0.177 in Jining Grey goats, respectively. The does with genotype AA had 0.78 （P〈0.05） or 0.64（P〈0.05） kids more than those with genotype AB or AC in Jining Grey goats, respectively.