【作者】 EL MOUJAHID EL MOSTAFA；

【导师】 杨宁； 陈思睿；

【作者基本信息】 中国农业大学 ， 动物遗传育种与繁殖， 2014， 博士

【摘要】 鸟类的生长、采食量与饲料转化率受多种遗传因素的影响。本研究在9个与体重(BW)、体增重(BWG)、采食量(FI)和饲料转化率(FCR)相关的候选基因(LEPR,PRKAB1,PRKAG2, PRKAG3,MTOR,PDPK1,NPY6R,INS与GH1)中选取了49个SNP,对来自两个品系(N202和N301)的共796只已知系谱的雄性黄羽肉鸡进行基因型检测,其中22个SNP通过了基因型质量控制。另外,本试验分别测量了个体的49日龄(BW49)和70日龄(BW70)的体重,以及49至70日龄之间的采食量。体增重和饲料转化率通过49至70日龄之间的体重与采食量计算得出。SNP位点与表型性状的关联分析结果如下：1.对于LEPR,结果表明rs14657368与两个品系中的体增重和饲料转化率都存在显著相关(P<0.05),rs13684613和rs14657336与两品系中的采食量均存在显著相关(P<0.05)。两品系中显著相关表现出的一致性,证实了这一结果。虽然rs13684616与两品系的采食量均存在相关(P<0.05),但是却具有相反的基因效应。而某些SNP-性状关联只在一个品系中检出：rs13684613、 rs14657336、rs13684616和rs13684623只与N202品系的体重存在显著相关(P<0.05),而rs14657368只与N301品系的体重存在显著相关(P<0.05)。此外,rs13684623只与N202品系的采食量存在显著相关(P<0.05),rs13684615只与N301品系的采食量存在显著相关(P<0.05),rs13684616只与N301品系的饲料转化率存在显著相关(P<0.05)。另外,rsl4657336、rs13684613、 rs13684615和rs13684616处于连锁不平衡状态(LD),单倍型关联分析表明基于这四个位点的LD域与N202品系的体重和采食量、N301品系的饲料转化率存在显著相关(P<0.05)。2.PRKAB1中的rs14094358和rs14094362只与N202品系的体重、体增重和采食量存在显著相关(P<0.05),rs14094361只与N301品系的采食量和饲料转化率存在显著相关(P<0.05)。rs14094363只与N301品系的饲料转化率存在显著相关(P<0.05)。对于PRKAG2来说,上述4个SNP只与单个品系的性状存在相关,这些SNP的基因型效应同样具有品系特异性。3.PRKAG2中的rs14133282只与N202品系的采食量存在显著相关(P<0.05),rs13535812只与N202品系的体重存在显著相关(P<0.05)。这些单一SNP的基因型效益具有品系特异性。4.PRKAG3中的rs13595570与N202品系的体重存在显著相关(P<0.05)并且与N301品系的采食量和饲料转化率存在显著相关(P<0.05)。结果说明这两个SNP的基因型效应具有品系特异性。5.rs14284557(mTOR)只与N202品系的采食量存在显著相关(P<0.05)。这种关联说明此单个SNP的基因型效应具有品系特异性。6.PDPK1中的Snp.23.302.41339.S.1和rs14075742与两品系的体重均具有显著相关(P<0.05)。这种显著相关在两个品系中表现出一致性,证实了这一结果。虽然Snp.23.302.41339.S.1和rs14075742与两品系的采食量相关(P<0.05),但是却表现出相反的基因效应。此外,Snp.23.302.41339.S.1和rs14075742只与N301品系的体增重存在显著相关(P<0.05)。因此,这两组体增重关联的单一SNP,其基因型效应具有品系特异性。7.NPY6R中的Snp.31.298.3106.S.1和rs14062577与N202品系的体重存在相关(P<0.05),rs14062576与N301品系的体重存在相关(P<0.05)。Snp.31.298.3106.S.1和rs14062576只与N301品系的采食量存在显著相关(P<0.05),rs14062577只与N202品系的采食量存在显著相关(P<0.05)。另外,Snp.31.298.3106.S.1只与N301品系的饲料转化率存在显著相关(P<0.05)。NPY6R的3个SNP只与一个品系中的性状相关。这些结果说明上述单个SNP的基因型效应具有品系特异性。8.在两个品系中rs13757636(INS)与采食量、饲料转化率和体重均存在显著相关(P<0.05)。这种显著相关在两个品系中表现出的一致性,证实了这一结果。9.GH中SNP-与性状的关联只存在于单一品系中,rs13401485确实与N301品系中的体重和采食量存在显著相关(P<0.05)。但是,Snp.101.6.287.S.1也与N202品系中的体重和采食量存在显著相关(P<0.05)。这一结果表明单个SNP的基因型效应存在品系特异性。总体来说,本次研究检测的9个基因的多态性(LEPR, PRKAB1, PRKAG2, PRKAG3, MTOR, PDPK1, NPY6R, INS与GH)与鸡的体重、体增重、采食量和饲料转化率存在相关。我们的发现证实了对调解生长,采食量和饲料转化率基因研究的重要性,并且提供了进一步探索的研究基础,检测到的多态性位点可能成为培育肉鸡的潜在遗传分子标记。更多还原

【Abstract】 Many genetic factors influence the growth, feed intake and feed efficiency of birds. In the current study we evaluated the association of49previously reported SNPs in9candidate genes (LEPR, PRKAB1, PRKAG2, PRKAG3, MTOR, PDPK1, NPY6R, INS, and GH) with body weight (BW), body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR).27SNPs with a very low minor allele frequency were removed due to genotype quality control and data filtering. The experimental population consisted of796pedigreed males from2genetically unrelated yellow meat-type chicken strains,335chickens for N202and461chickens for N301. Body weight at49(BW49) and70days of age (BW70) and FI (from49to70days of age) were measured individually. BWG and FCR were calculated based on BW and FI in the interval between49to70days. The results for each gene are as followings:1. LEPR:rs14657368was significantly associated with BWG and FCR in both strains (P<0.05), and together rs13684613and rs14657336were significantly associated with FI in both strains (P<0.05). These significant associations were consistent in both strains, and validated the results. However, rs13684616was associated with FI in both strains (P<0.05) but has opposite genetic effects among the two strains. In addition, some of the SNP-trait associations were detected in only one strain. Indeed, rs13684613, rsl4657336, rsl3684616, and rs13684623were significantly associated with BW only in N202strains (P<0.05) and rs14657368was significantly associated with BW only in N301strain (P<0.05). Furthermore, rs13684623was significantly associated with FI only in the N202strain (P<0.05), rs13684615was significantly associated with FI just in the N301strain (P<0.05) and rs13684616was significantly associated with FCR just in the N301strain (P<0.05). Besides, haplotypes for the strong LD block based on rs14657336, rsl3684613, rs13684615and rs13684616were reconstructed and haplotype association analysis indicated that the LD block was significantly associated with BW and FI in the N202strain and FCR in the N301strain (P<0.05).2. PRKAB1:rs14094358and rs14094362were significantly associated with BW, BWG and FI only in N202strain (P<0.05) and rs14094361was significantly associated with FI and FCR just in N301strain (P<0.05). As well, rs14094363was significantly associated with FCR only in the N301strain (P<0.05). For the PRKAB1gene, the four SNPs were associated with traits only in one strain and the genotype effects of the SNPs were strain-specific.3. PRKAG2:the results implied that rs14133282was significantly associated with FI only in N202strain (P<0.05) and rs13535812was significantly associated with BW just in N202strain (P<0.05). The genotype effects of those SNPs were strain-specific.4. PRKAG3:rs13595570was significantly associated with BW in N202strain (P<0.05) and significantly associated with FI and FCR in N301strain (P<0.05). The results suggested that the genotype effects of this SNP were strain-specific.5. mTOR:rs14284557was significantly associated with FI just in N202strain (P<0.05). This association implies that genotype effects of this SNP were strain specific.6. PDPK1:Snp.23.302.41339.S.1and rs14075742were significantly associated with BW in both strains (P<0.05). These significant associations were consistent in both strains, and validated the results. However, Snp.23.302.41339.s.1and rs14075742were associated with FI in both strains (P<0.05) but with opposite genetic effects in the two strains. Besides, Snp.23.302.41339.s.1and rs14075742were significantly associated with BWG only in N301strains (P<0.05). Thus, the genotype effects of the two SNPs for BWG were strain-specific.7. NPY6R:Snp.31.298.3106.S.1and rs14062577were significantly associated with BW in N202strain (P<0.05) and rs14062576was significantly associated with BW in N301strain (P<0.05). As well, Snp.31.298.3106.S.1and rs14062576were significantly associated with FI only in N301strain (P <0.05) and rs14062577was significantly associated with FI just in the N202strain (P<0.05). Moreover, Snp.31.298.3106.S.1was significantly associated with FCR just in the N301strain (P<0.05). The three SNPs in NPY6R were associated with traits only in one strain. These results indicated that genotype effects of those SNPs were strain-specific.8. INS:rs13757636was significantly associated with FI, FCR and BW in both strains (P<0.05). These significant associations were consistent in both strains, and validated the results.9. GH:the detected SNP-trait associations were in only one strain. Indeed, rs13401485was significantly associated with BW and FI in N301strain (P<0.05). However, Snp.101.6.287.S.1was significantly associated with BW and FI in N202strain (P<0.05). The results suggested that genotype effects of those SNPs were strain specific.As a whole, the examined polymorphisms of the9genes (LEPR, PRKAB1, PRKAG2, PRKAG3, MTOR, PDPK1, NPY6R, INS, and GH) were associated with BW, BWG, FI, and feed efficiency in chicken. Our findings confirm the importance of the studied genes in regulating growth, feed intake and feed efficiency and provide research basis for further investigations. The studied polymorphisms might be used as potential breeding genetic markers in meat-type chicken.更多还原