山羊VPS13C和EIF4G1基因多态性及其与产奶性状关联性分析

摘要

为了探究VPS13C和EIF4G1基因与奶山羊产奶性状的关系,以吐根堡和崂山奶山羊为试验组,辽宁绒山羊、日土白绒山羊、班戈白绒山羊和南疆绒山羊为对照组,采用PCR产物直接测序方法,检测VPS13C基因外显子10、33和内含子10以及EIF4G1基因外显子18和24上的单核苷酸多态性在不同山羊品种中的分布.结果表明,在VPS13C基因外显子10、33和内含子10上分别检测到1、1和3个多态位点.其中,g.22885C＞A、g.72809G＞A位点均导致氨基酸变化.在该基因中发现2个在奶用和非奶用山羊群体中共有的单体型,分别为ACAG(奶山羊中63.7％;非奶用山羊中21.2％)和CTGT(奶山羊中36.3％;非奶用山羊中78.1％),说明单体型ACAG可能与山羊的产奶性状相关.在EIF4G1基因外显子18和24上各发现1个多态位点,其中g.12301A＞G位点导致氨基酸变化,g.9003G＞A住点不改变氨基酸.g.9003G＞A位点在崂山奶山羊上存在AA和AG两种基因型,与日均产奶量关联分析显示,AA基因型个体的日均产奶量显著高于AG基因型个体(P=O.021).研究结果提示:VPS13C和EIF4G1基因均可能是与山羊产奶性状有一定的相关性,EIF4G1基因中g.9003G＞A位点与奶山羊高产奶量之间存在显著相关性.%In order to analyze the association between polymorphisms of the VPS13C and EIF4G1 gene and milk traits of dairy goat,Toggenburg and Laoshan dairy goats were selected as the experimental group,and Liaoning,Ritu,Bange,Nanjiang cashmere goats were used as the control group.In this study,polymorphisms of exon 10,33 and intron 10 of VPS13C and exon 18,24 of EIF4G1 were detected by DNA sequencing method.The results showed that,one and three polymorphic loci were detected in exon 10,33 and intron 10 of VPS13C gene respectively.Among them,g.22885C＞A and g.72809G＞A caused the changes in amino acids.Association analysis showed that there were no significant correlation between the different genotypes of the five polymorphic loci and the average daily milk yield of Laoshan dairy goats.However,two common haplotypes were identified in all studied goat populations.Haplotype ACAG in LD block was dominant in dairy goat (63.7％) and segregated at higher frequency than that in non-dairy goat (21.2％),indicating that the association of ACAG haplotype to the milk production performance of dairy goats.In addition,two polymorphic loci were found in exon 18 and 24 of EIF4G1 gene.Mutation g.12301A＞G resulted in amino acid change,and mutation g.9003G＞A did not cause any amino acid change.In Laoshan dairy goat,g.9003G＞A assumed two genotypes named AA and AG respectively.The association analysis of genotypes and average daily milk yield revealed that individuals with genotype AA were significantly higher than those with genotype AG(P=0.021).These findings suggested that VPS13C and EIF4G1 gene could be the candidate genes of milk traits in dairy goat,and the g.9003G＞A loci of EIF4G1 might be an effective molecular marker for milk performance of dairy goat.