Molecular breeding accelerates animal breeding and improves efficiency by utilizing genetic mutations. Structural variations (SVs), a significant source of genetic mutations, have a greater impact on phenotypic variation than SNPs. Understanding SV functional mechanisms and obtaining precise information are crucial for molecular breeding. In this study, association analysis revealed significant correlations between 198-bp SVs in the GSTA2 promoter region and abdominal fat weight, intramuscular fat content, and subcutaneous fat thickness in chickens. High expression of GSTA2 in adipose tissue was positively correlated with the abdominal fat percentage, and different genotypes of GSTA2 exhibited varied expression patterns in the liver. The 198-bp SVs regulate GSTA2 expression by binding to different transcription factors. Overexpression of GSTA2 promoted preadipocyte proliferation and differentiation, while interference had the opposite effect. Mechanistically, the 198-bp fragment contains binding sites for transcription factors such as C/EBPα that regulate GSTA2 expression and fat synthesis. These SVs are significantly associated with chicken fat traits, positively influencing preadipocyte development by regulating cell proliferation and differentiation. Our work provides compelling evidence for the use of 198-bp SVs in the GSTA2 promoter region as molecular markers for poultry breeding and offers new insights into the pivotal role of the GSTA2 gene in fat generation.

试验旨在分析GSTA2基因的SNPs和杏花鸡与隐性白洛克鸡F2群体的肉质、生长和屠体性状的相关性.试验采用Sanger测序从359个杏花鸡与隐性白洛克鸡F2群体的基因组序列中筛选到4个GSTA2基因的SNPs,均位于5'UTR区域.利用SPSS 22.0软件对4个SNPs与杏花鸡和隐性白洛克鸡F2群体的经济性状进行了关联分析.结果显示:4个SNPs与杏花鸡和隐性白洛克鸡F2群体的体重、胫长、肤色等性状显著相关.对4个SNPs进行单倍型分析发现SNP1、SNP3、SNP4组成的单倍型AGAGTT与鸡的翅重有显著相关性,SNP2、SNP4组成的单倍型GGTT与鸡的胫长有显著相关性.结果表明GSTA2基因的SNPs显著影响鸡的经济性状,可以作为鸡经济性状选育的候选分子标记.

Background : Ras and Rab interactor 2 ( RIN2 ) gene, encoding RAS and Rab interacting protein 2, can interact with GTP-bound Rab5 and participate in early endocytosis. Deletion of RIN2 may impair Rab5-related endosome signaling, leading to abnormal phenotypes. However, no research has been reported on the functions of RIN2 related to animal production. Results: A 61-bp insertion/deletion (indel) in the RIN2 intron region in this study. The genotype analysis of mutation sites was performed on 550 individuals from 7 different chicken breeds, and it was found that the indel exists in each breed and the local breed chickens are mainly DD genotypes. Correlation analysis of the indel with growth traits and carcass traits of the F 2 population of Xinghua and White Recessive Rock chicken showed that the RIN2 61-bp deletion mutation site was significantly correlated with abdominal fat weight, fat width and hatching weight traits ( P < 0.05). RIN2 mRNA was expressed in all test tissues, and the expression level of abdominal fat was higher than that in other tissues. In addition, it was further found that the expression level of type II RIN2 mRNA in abdominal fat was significantly different from that of ID type and DD type ( P < 0.05). Conclusion: The results showed that the mutation was closely related to the abdominal fat-related and hatching weight traits of chickens, which may have certain reference value for molecular marker-assisted selection of chickens.

Golgin subfamily B member 1 (GOLGB1) gene encodes the coat protein 1 vesicle inhibiting factor, giantin. Previous study showed that mutations of the GOLGB1 gene are associated with dozens of human developmental disorders and diseases. However, the biological function of GOLGB1 gene in chicken is still unclear. In this study, we detected a novel 65-bp insertion/deletion (indel) polymorphism in the chicken GOLGB1 intron 5. Association of this indel with chicken growth and carcass traits was analyzed in a yellow chicken population. Results showed that this 65-bp indel was significantly associated with chicken body weight (p < 0.05), highly significantly associated with neck weight, abdominal fat weight, abdominal fat percentage and the yellow index b of breast (p < 0.01). Analysis of genetic parameters indicated that “I” was the predominant allele. Except for the yellow index b of breast, II genotype individuals had the best growth characteristics, by comparison with the ID genotype and DD genotype individuals. Moreover, the mRNA expression of GOLGB1 was detected in the liver tissue of chicken with different GOLGB1 genotypes, where the DD genotype displayed high expression levels. These findings hinted that the 65-bp indel in GOLGB1 could be assigned to a molecular marker in chicken breeding and enhance production in the chicken industry.