College of animal science and technology, Henan Agricultural University, Zhengzhou, Henan Province 4500046, China; Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources, Zhengzhou, Henan Province 450046, China.
Henan Husbandry Breau, Zhengzhou 450008, China.
Res Vet Sci. 2023 Feb;155:115-123. doi: 10.1016/j.rvsc.2022.12.001. Epub 2022 Dec 9.
Alkaline phosphatase (ALP) is a marker of osteoblast maturation and an important indicator of bone metabolism. The activity of ALP can reflect the bone metabolism and growth traits of animals, so the polymorphism affecting ALP expression deserves further study. In this study, we identified an SNP site in ST3GAL4 found by genome-wide association studies (GWAS) in previous studies, 8 SNPs were also identified by DNA sequencing. Interestingly, there were 4 SNPs (rs475471G > A, rs475533C > T, rs475621A > G, rs475647C > A) completely linked by haplotype analysis. Therefore, we selected a tag SNP rs475471G > A to further analyze the ALP level of different genotypes in Hubbard leg disease population and an F chicken resource population produced by Anka and Gushi chickens and carried out population genetic analysis in 18 chicken breeds. Association analysis showed that this QTL within ST3GAL4 was highly correlated with ALP level. The mutant individuals with genotype AA had the highest ALP level, followed by GA and GG carriers. The mutant individual carriers of AA and GA genotype had higher values for body weight (BW), chest width (CW), body slanting length (BSL), pelvis width (PW) at 4-week, the semi-evisceration weight (SEW), evisceration weight (EW) and Leg weight (LW) than GG genotypes. The amplification and typing of 4852 DNA samples from 18 different breeds showed GG genotype mainly existed in egg-type chickens and dual-type chickens, while the AA genotype was mainly distributed in commercial broilers and F resource population. The individual carriers of the AA genotype had the highest ALP and showed better growth performance. Besides, tissue expression analysis used Cobb broiler showed significant differences between different genotypes in the spleen and duodenum. Taken together, this was the first time to determine 9 SNPs within ST3GAL4 related to ALP in chickens, 4 of them were complete linkage with each other, which provides useful information on the mutation of ST3GAL4 and could predict the serum ALP level of chicken early and as an effective potential molecular breeding marker for chickens.
碱性磷酸酶（ALP）是成骨细胞成熟的标志物，也是骨代谢的重要指标。ALP 的活性可以反映动物的骨骼代谢和生长特性，因此，影响 ALP 表达的多态性值得进一步研究。在本研究中，我们鉴定了先前全基因组关联研究（GWAS）发现的 ST3GAL4 中的一个 SNP 位点，通过 DNA 测序还鉴定了另外 8 个 SNP。有趣的是，通过连锁不平衡分析，发现有 4 个 SNP（rs475471G>A、rs475533C>T、rs475621A>G、rs475647C>A）完全连锁。因此，我们选择了一个标签 SNP rs475471G>A 来进一步分析 Hubbard 腿病群体和由 Anka 和 Gushi 鸡产生的 F 鸡资源群体中不同基因型的 ALP 水平，并在 18 个鸡品种中进行了群体遗传分析。关联分析表明，ST3GAL4 内的这个 QTL 与 ALP 水平高度相关。基因型为 AA 的突变个体的 ALP 水平最高，其次是 GA 和 GG 携带者。AA 和 GA 基因型的突变个体在 4 周时的体重（BW）、胸宽（CW）、体斜长（BSL）、骨盆宽（PW）、半净膛重（SEW）、全净膛重（EW）和腿重（LW）值更高。对来自 18 个不同品种的 4852 个 DNA 样本进行扩增和分型，结果表明 GG 基因型主要存在于蛋鸡和兼用鸡中，而 AA 基因型主要分布在商业肉鸡和 F 资源群体中。AA 基因型的个体携带者的 ALP 水平最高，生长性能也更好。此外，使用 Cobb 肉鸡进行的组织表达分析显示，不同基因型在脾脏和十二指肠之间存在显著差异。综上所述，这是首次在鸡中确定与 ALP 相关的 ST3GAL4 内的 9 个 SNP，其中 4 个 SNP 彼此完全连锁，这为 ST3GAL4 的突变提供了有用的信息，并可早期预测鸡的血清 ALP 水平，是一种有效的潜在分子鸡育种标记。
