National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China.
Beijing Zhongnongbangyang Layer Breeding Co., Ltd, Beijing, 100083, China.
BMC Genomics. 2023 Nov 22;24(1):704. doi: 10.1186/s12864-023-09632-7.
Eggshell speckle phenotype is an important trait in poultry production because they affect eggshell quality. However, the genetic architecture of speckled eggshells remains unclear. In this study, we determined the heritability of eggshell speckles and conducted a genome-wide association study (GWAS) on purebred Rhode Island Red (RIR) hens at 28 weeks to detect potential genomic loci and candidate genes associated with eggshell speckles.
The heritability of eggshell speckles was 0.35 at 28 weeks, and the speckle level is not related to other eggshell quality traits in terms of phenotypic correlation. We detected 311 SNPs (6 significantly, and 305 suggestively associated) and 39 candidate genes associated with eggshell speckles. Based on the pathway analysis, the 39 candidate genes were mainly involved in alpha-linolenic acid metabolism, linoleic acid metabolism, ether lipid metabolism, GnRH signaling pathway, vascular smooth muscle contraction, and MAPK signaling pathway. Ultimately, ten genes, LOC423226, SPTBN5, EHD4, LOC77155, TYRO3, ITPKA, DLL4, PLA2G4B, PLA2G4EL5, and PLA2G4EL6 were considered the most promising genes associated with eggshell speckles that were implicated in immunoregulation, calcium transport, and phospholipid metabolism, while its function in laying hens requires further studies.
This study provides new insights into understanding the genetic basis of eggshell speckles and has practical application value for the genetic improvement of eggshell quality.
蛋壳斑纹表型是家禽生产中的一个重要特征，因为它们影响蛋壳质量。然而，斑驳蛋壳的遗传结构仍不清楚。本研究在 28 周龄时测定了纯系罗得岛红（RIR）母鸡蛋壳斑纹的遗传力，并进行了全基因组关联研究（GWAS），以检测与蛋壳斑纹相关的潜在基因组位点和候选基因。
28 周时蛋壳斑纹的遗传力为 0.35，斑纹水平与其他蛋壳质量性状在表型相关性方面没有关系。我们检测到 311 个 SNP（6 个显著，305 个提示性相关）和 39 个与蛋壳斑纹相关的候选基因。基于通路分析，这 39 个候选基因主要参与α-亚麻酸代谢、亚油酸代谢、醚脂代谢、GnRH 信号通路、血管平滑肌收缩和 MAPK 信号通路。最终，十个基因 LOC423226、SPTBN5、EHD4、LOC77155、TYRO3、ITPKA、DLL4、PLA2G4B、PLA2G4EL5 和 PLA2G4EL6 被认为是与蛋壳斑纹最相关的最有希望的基因，这些基因参与免疫调节、钙转运和磷脂代谢，但其在蛋鸡中的功能还需要进一步研究。
本研究为了解蛋壳斑纹的遗传基础提供了新的见解，对蛋壳质量的遗传改良具有实际应用价值。
