Genome-wide association analysis of growth traits in Tianzhu White Yak

Identifying key markers or genes associated with growth traits in Tianzhu White Yak is crucial for breeding. In this study, Low‑coverage resequencing was performed on 536 Tianzhu White Yaks representing distinct growth stages (1 year, 2.5 years, and ≥ 4 years), and four growth‑related traits—body weight (BW), body height (BH), body oblique length (BL), and chest circumference (CC)—were measured. Genome-wide association studies (GWAS) were conducted to identify candidate genes associated with these four body measurements, thereby laying the foundation for subsequent studies on the biological functions of these genes. After genotype imputation and quality control, a total of 24,383,269 SNPs were retained for subsequent analysis. A total of 366 significant SNP loci were identified, which were annotated to 32 candidate genes associated with body conformation traits, such as PLCB1 , SAR1B , and SRSF6 for body weight; BRPF3 , MAPK13 , and ZNF76 for body height; ABCD3 and NTM for body oblique length; and LMNTD1 and ACVR1 for chest circumference. Functional analysis revealed that multiple candidate genes are involved in key biological processes, including negative regulation of the G1/S transition of the mitotic cell cycle and fatty acid beta-oxidation. Notably, TEAD3 , ZNF76 , and RBL1 were significantly enriched in the transcription regulator complex, a cellular component that may influence cell proliferation, differentiation, and tissue formation. In this study, a series of SNPs and candidate genes associated with growth traits were identified through low‑overage resequencing combined with GWAS analysis, which will facilitate the development and utilization of Tianzhu White Yak resources.