Copy number variation of ZNF280BY across eight sheep breeds and its association with testicular size of Hu sheep.

The zinc finger protein 280B-like, Y-linked ZNF280BY is a bovid-specific Y chromosome gene, playing important roles in testicular development and male fertility. In this study, we found that the ovine ZNF280BY was highly expressed in the testis and significantly upregulated during testicular development. The copy number of ZNF280BY was negatively correlated with testicular size in Hu sheep. Our results demonstrated that the CNV of ZNF280BY could be used as an important candidate marker for selecting elite rams at an early stage in Hu sheep.