Plymorphisms Of Gnrhr,gdf9&bmp15 Genes And Their Relationship With Prolificacy In Gansu Meat Sheep New Breed Population

Gansu meat sheep new breed population (204)and Poll Dorset(32) which come from Yongchang meat breeding farm of Gansu province were studied as experimental material. Polymorphisms of Growth differentiation factor(GDF9)gene, Bone morphogenetic protein 15(BMP15)gene and Gonadotropin releasing hormone receptor(GnRHR) gene were detected, The polymorphisms of exonl & exon2 of GDF9, exon2 & exon3 of GnRHR and exon1&exon2 of BMP 15 in new breed population sheep were analyzed by PCR-SSCP. We attempt to find the link of high productivity and those candidate genes, and provide some scientific evidence for basic genetic research on high productivity of new breed population sheep.The results were as following:(1)The optimum method of PCR-SSCP about GDF9, BMP15(GDF9B)and GnRHR gene had been established, and the best condition of PCR-SSCP had been found out.(2) There were three genotype(AA,AB and BB) in BMP15 gene exonl of new breed population sheep detected by primerl.In new breed sheep, frequencies of AA,AB and BB genotypes were 0.618(126),0.328(67),0.054(11),respectively. While there was one genotype(AA) detected in Poll Dorset.The polymorphic fragment amplified was sequenced. The result showed that CTT was lost at cDNA 28 of BMP15 gene.So the results indicated that the sequence of exonl of BMP15 gene was polymorphism, and the difference of LSM for lambing numbers among AA,BB and AB was non-significant(P >0.05).So exonl of BMP15 gene may not be the functional domain that affects the prolificacy in new breed sheep.(3) There were two genotypes (CC and CD) detected by primer7 in GDF9 gene exonl of new breed population sheep, frequencies of CC and CD genotypes were 0.946(193),0.054(11),respectively. The polymorphic fragment amplified was sequenced. The result showed that there was one nucleotide mutation(G→A) at cDNA 260 of GDF9 gene, the mutation results amino acid change (Arg→His).and the difference of LSM for lambing numbers among CC and CD was significant(P<0.05).An other mutation(G→A) was found in GDF9 exon2 at cDNA 994.the mutation results amino acid change (Val→Ile),but the difference of LSM for lambing numbers among EE and FF was non-significant(P>0.05).(4) There were there genotypes (GG,GH and HH) detected by primer12 in GnRHR gene exon2 of new breed population sheep, frequencies of GG, GH and HH genotypes were 0.784(160),0.206(42),0.010(2), respectively. The polymorphic fragment amplified was sequenced.The results showed that there was one nucleotide mutation(G→C) at cDNA 198 of GnRHR gene, the mutation results amino acid change (Gly→Arg).and the difference of LSM for lambing numbers among GG and HH was significant(P<0.01). An other mutation(A→G) was found in GnRHR exon3 at cDNA 257. The mutation results amino acid change (Gin→AArg),the difference of LSM for lambing numbers among MM and MN wassignificant(P<0.05).