Integrated analyses of genomic and transcriptomic data reveal candidate variants associated with carcass traits in Huaxi cattle 1

Cattle carcass traits are economically important in the beef industry. In the present study, we identified 184 significant genes and 822 alternative genes for 7 carcass traits using genome-wide association studies (GWASs) in 1566 Huaxi beef cattle. We then identified 5,860 unique cis-genes and 734 trans-genes in 227 longissimus dorsi muscle (LDM) samples to better understand the genetic regulation of gene expression. Our integration study of the GWAS and cis-eQTL analysis detected 13 variants regulating 12 identical genes, in which one variant was also detected in fine-mapping analysis. Moreover, using a transcriptome-wide association study (TWAS), we identified 4 genes (TTC30B, HMGA1, PRKD3 and FXN) that were significantly related to carcass chest depth (CCD), carcass length (CL), carcass weight (CW) and dressing percentage (DP). This study identified variants and genes that may be useful for understanding the molecular mechanism of carcass traits in beef cattle.