中国肉用西门塔尔牛生长曲线参数的全基因组关联分析

旨在通过对中国肉用西门塔尔牛纵向体重性状的全基因组关联分析(genome-wide association study,GWAS),定位与肉牛生长发育性状显著关联的候选基因.本研究利用808头中国肉用西门塔尔牛公牛0、6、12、18月龄的纵向体重数据,采用Gompertz、Logistic和Brody 3种非线性模型拟...

Genome-wide Association Study of Growth Curve Parameters in Chinese Simmental Beef Cattle

The objective of this study was to explore candidate genes which are significantly associated with growth and development traits of beef cattle by performing genome-wide association study (GWAS) for body weight longitudinal data of 808 Chinese Simmental beef cattle. The longitudinal body weight data of 808 Chinese Simmental beef bulls aged 0, 6, 12 and 18 months were used to fit the individual body weight prediction model using 3 nonlinear models (Gompertz model, Logistic model and Brody model), and the parameters A (mature body weight), b (time-scale parameter) and K (maturity rate) were estimated. Then, the parameter values were used as phenotypes. After the quality control using the BovineHD Beadchip (770K), 671 991 SNPs were generated. GAPIT was used for association analysis, combined with gene annotation to identify candidate genes associated with development traits of beef cattle. Gompertz model with the highest goodness of fit (R²=0.954) was selected to determine the parameter estimates. A total of 9, 49 and 7 significant SNPs associated with parameters A, b and K were identified by GWAS, respectively. These SNPs were mainly mapped on BTA 2, 3, 7, 9, 11, 14, 22 and 25. Gene annotation results showed that PLIN3, KCNS3, ANGPTL2 and ALPL were associated with fat deposition process, and KCNS3 was considered as a candidate gene for intramuscular fat content; IGF-1, TMCO1, PRKAG3 and SHISA9 were associated with growth and development, and IGF-1 was reported to be central to the growth and development process; ASPH was involved in regulating carcass development and meat quality traits of beef cattle. In this study, the estimated parameters of the weight prediction model were used as phenotypes for GWAS, and some candidate genes associated with growth and development traits were identified, which provided a reference for other longitudinal data studies and new candidate molecular markers for regulating the growth and development of beef cattle to improve meat production in breeding.