Performance Measurement and Comparative Transcriptome Analysis Revealed the Efforts on Hybrid Improvement of Qinchuan Cattle

Crossbreeding can provide productive gains through heterosis, however, surveys about the effects of crossbreeding through global transcriptomic sequencing are few. This study revealed that Angus x Qinchuan cattle (AQF) have improved performance characteristics compared to Qinchuan cattle (QCF). We performed RNA-seq on the subcutaneous fat tissue of QCF and AQF. More than 42.2 million clean reads were obtained in each sample. We detected 40 and 21 breed-specific highly expressed genes (FPKM > 500) in QCF and AQF, respectively. Furthermore, a total of 353 differentially expressed genes (DEGs, |log2 ratio| >= 1 and Probability >= 0.8) were found between these two groups, of which 227 genes were upregulated in AQF and 126 genes were upregulated in QCF. Functional enrichment analyses showed that breed-specific highly expressed genes and DEGs were closely related to terms such as development in AQF, and adaption or immune in QCF. In addition, we also identified the novel transcript units, alternative splicing events, single-nucleotide polymorphisms and Indels. Our results revealed differences in inherent characteristics and genetic differences when comparing QCF with AQF.