| 摘要: |
| 【 目的】解析通用转录因子ⅡA亚基 1（general transcription factor ⅡA subunit 1，GTF2A1）基因对鸡产蛋性状的遗传效应，筛选与其显著相关的单核苷酸多态性（single nucleotide polymorphism，SNP）标记，为苏禽4号母系（M系）产蛋性能的分子标记辅助育种提供依据。【 方法】以384只苏禽4号母系（M系）为试验对象，采用Sanger测序与Sequenom MassARRAY技术对GTF2A1基因进行SNP筛查。利用Haploview v4. 1分析连锁不平衡（linkage dis?equilibrium，LD），基于一般线性模型（general linear model，GLM）进行SNP位点及单倍型与产蛋性状的关联分析，并通过MEME Suite预测SNP对转录因子结合的影响。用GOMO对GTF2A1基因SNP位点保守基序进行功能预测， 【结果】共检出2个SNP位点：g.40334089G>C（位于5′ UTR，为颠换突变）和g.40341114A>G（位于外显子3，为同义突变）。2 位点均符合哈代-温伯格平衡（P>0.05），且呈中度多态性。关联分析表明，g.40334089G>C 位点GG基因型个体与g.40341114A>G位点AA基因型个体的开产日龄和300日龄产蛋数均显著优于其他基因型个体（P<0.05）。2个SNP位点处于强连锁不平衡状态，形成H1（GA）、H2（CG）、H3（GG）等3种单倍型，其中 H1H1（GGAA）组合个体的300日龄产蛋数与开产日龄表现较优。g.40341114A>G位点有一个保守基序（CCTGCAGCTGGTCAG?CAGCAGCCR（A/G）CAGC），该保守基序参与了小GTP酶介导的信号转导、蛋白质转运、葡萄糖代谢过程等生物过程及趋化因子活性、GTP结合等分子功能；g.40334089G>C位点没有保守基序。g.40341114A>G位点A→G突变能够增强保守基序与转录因子Myod1的结合能力，G→A突变可增强保守基序与转录因子 REST 和 PPARG 的结合能力。【 结论】GTF2A1基因中g.40334089G>C和g.40341114A>G位点均与产蛋性状显著相关，其中单倍型组合H1H1（GGAA）为改善开产日龄和300日龄产蛋数的优势遗传标记，可作为苏禽4号母系（M 系）分子标记辅助育种的核心依据。 |
| 关键词: 鸡 GTF2A1基因 产蛋性状 单核苷酸多态性 |
| DOI：10. 13207/j. jnwafu. 2026. 11. 002 |
| 分类号: |
| 基金项目:现代农业产业技术体系建设专项（CARS-41-Z21）；江苏省种业振兴揭榜挂帅项目（JBGS（2021）109） |
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| Screening and bioinformatics analysis of SNPs in the chicken GTF2A1 gene and their association with egg⁃laying traits |
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LI Chunmiao, HUANG Huayun, WANG Qianbao, WU Zhaolin, HUANG Zhengyang, KONG Linglin, HU Yangyang, ZHAO Zhenhua
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Jiangsu Institute of Poultry Sciences，Yangzhou，Jiangsu 225125，China
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| Abstract: |
| 【 Objective】This study aimed to elucidate the genetic effects of the general transcription factor Ⅱ A Subunit 1（ GTF2A1） gene on egg-laying traits in chickens，and screen single nucleotide polymorphism （SNP） markers significantly associated with these traits，to provide a basis for marker-assisted selection to im?prove egg-laying performance in the maternal line（M line） of Suqin No. 4 chickens.【Method】A total of 384 hens from the Suqin No.4 maternal line were used as experimental subjects. SNP screening of the GTF2A1 gene was performed by using Sanger sequencing and Sequenom MassARRAY technology. Haploview v4. 1 was employed for linkage disequilibrium（LD） analysis. Association analyses between SNP loci/haplotypes and egg-laying traits were conducted based on a general linear model（GLM）.The potential impact of SNP on transcription factor binding was predicted by using the MEME Suite. Function prediction of conserved motifs for SNP loci in the GTF2A1 gene was performed by using GOMO. 【Result】Two SNP loci were identified：g.40334089G>C（ located in the 5′ UTR，a transversion mutation） and g. 40341114A>G（ located in exon 3，a synonymous mutation）. Both loci were in Hardy-Weinberg equilibrium（P>0.05） and exhibited moderate poly-morphism.Association analysis revealed that individuals with the GG genotype at the g. 40334089G>C locus and individuals with the AA genotype at the g. 40341114A>G locus had significantly better performance in age at first egg and the total number of eggs laid at the age of 300 days，compared to individuals with other genotypes （P<0.05）.The two SNP loci were in strong linkage disequilibrium， forming three haplotypes：H1（GA），H2（CG），and H3（GG），with H1H1（GGAA） diplotype individuals showing better performance in age at first egg and the total number of eggs laid at the age of 300 days. The g. 40341114A>G locus contained one conserved motif（ CCTGCAGCTGGTCAGCAGCAGCCR（A/G）CAGC），which was involved in biological processes such as small GTPase-mediated signal transduction，protein transport，and glucose metabolic process，as well as molecular functions including chemokine activity and GTP binding. No conserved motif was identified in the g. 40334089G>C locus. The A→G mutation at the g. 40341114A>G locus could enhance the binding affinity of the conserved motif to the transcription factor Myod1，while the G→A mutation could enhance its binding affi-nityto transcription factors REST and PPARG.【Conclusion】The g. 40334089G>C and g. 40341114A>G loci in the GTF2A1 gene are significantly associated with egg-laying traits. The H1H1（GGAA） diplotype serves as a favorable genetic marker for improving age at first egg and the total number of eggs laid at the age of 300 days，and can be used as a core basis for marker-assisted selection in the maternal line（M line） of Suqin No. 4 chickens. |
| Key words: chicken GTF2A1 gene egg-laying traits single nucleotide polymorphism |
