Jiang Bingjie, Tao Yifan, Tao Wenjing, Lu Siqi, Badran Mohamed Fekri, Saleh Moustafa Hassan Lotfy, Aboueleila Rahma Halim Mahmoud, Xu Pao, Qiang Jun, Liu Kai
Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center of Chinese Academy of Fishery Sciences, Wuxi 214082, China.
Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), School of Life Sciences, Southwest University, Chongqing 400715, China.
Int J Mol Sci. 2025 Jul 5;26(13):6492. doi: 10.3390/ijms26136492.
Growth traits are the most important economic traits in red tilapia ( spp.) production, and are the main targets for its genetic improvement. Increasing salinity levels in the environment are affecting the growth, development, and molecular processes of aquatic animals. Red tilapia tolerates saline water to some degree. However, few credible genetic markers or potential genes are available for choosing fast-growth traits in salt-tolerant red tilapia. This work used genome-wide association study (GWAS) and RNA-sequencing (RNA-seq) to discover genes related to four growth traits in red tilapia cultured in saline water. Through genotyping, it was determined that 22 chromosomes have 12,776,921 high-quality single-nucleotide polymorphisms (SNPs). One significant SNP and eight suggestive SNPs were obtained, explaining 0.0019% to 0.3873% of phenotypic variance. A significant SNP peak associated with red tilapia growth traits was located on chr7 (chr7-47464467), and was identified as the candidate gene in this region. A total of 501 differentially expressed genes (DEGs) were found in the muscle of fast-growing individuals compared to those of slow-growing ones, according to a transcriptome analysis. Combining the findings of the GWAS and RNA-seq analysis, 11 candidate genes were identified, namely , , , , , , , , , , and . These genes were involved in 'other types of O-glycan biosynthesis', 'glycine, serine and threonine metabolism', 'glycolysis/gluconeogenesis', 'mucin-type O-glycan biosynthesis' and 'purine metabolism signaling' pathways. We have developed molecular markers to genetically breed red tilapia that grow quickly in salty water. Our study lays the foundation for the future marker-assisted selection of growth traits in salt-tolerant red tilapia.
生长性状是红罗非鱼（ spp.）生产中最重要的经济性状，也是其遗传改良的主要目标。环境中盐度水平的升高正在影响水生动物的生长、发育和分子过程。红罗非鱼在一定程度上耐受盐水。然而，在耐盐红罗非鱼中，用于选择快速生长性状的可靠遗传标记或潜在基因很少。本研究利用全基因组关联研究（GWAS）和RNA测序（RNA-seq）来发现与在盐水中养殖的红罗非鱼四种生长性状相关的基因。通过基因分型，确定22条染色体上有12,776,921个高质量单核苷酸多态性（SNP）。获得了1个显著SNP和8个暗示性SNP，解释了0.0019%至0.3873%的表型变异。一个与红罗非鱼生长性状相关的显著SNP峰值位于chr7（chr7-47464467）上，并被确定为该区域的候选基因。根据转录组分析，与生长缓慢的个体相比，在生长快速的个体肌肉中总共发现了501个差异表达基因（DEG）。结合GWAS和RNA-seq分析的结果，鉴定出11个候选基因，即 、 、 、 、 、 、 、 、 、 和 。这些基因参与了“其他类型的O-聚糖生物合成”、“甘氨酸、丝氨酸和苏氨酸代谢”、“糖酵解/糖异生”、“粘蛋白型O-聚糖生物合成”和“嘌呤代谢信号”通路。我们已经开发了分子标记，用于对在咸水中快速生长的红罗非鱼进行遗传育种。我们的研究为未来耐盐红罗非鱼生长性状的标记辅助选择奠定了基础。
