Comparison of copy number variation profile in sheep with Holstein breed

The aim of this study was to compare copy number variation (CNV) in some Italian sheep breeds with Holstein cows. Blood samples were collected form 580 Holstein bulls and 360 different Italian sheep breeds and then DNA was extracted. The SNPs genotypes across the genome were determined by ovine and bovine 50K BeadChip in both species. By PennCNV, the 904 CNV with mean and median size of 154.7 kb and 103.7 kb in sheep and 744 CNV with mean and median of 213.7 kb and 124.5 kb in Holstein were detected, respectively. A total length of this variation were 8.5 Mb in sheep and was 80 Mb in cattle. After merging similar regions, the 35 and 141 non- unique copy number variation regions (CNVR) were detected in sheep and cows, respectively which 20% of sheep’s CNVRs overlapped with cattle’s CNVRs. In addition to, these regions in Sheep genome were partially or completely overlapped with 40 RefGen & 62 QTL in cattle and 110 RefGen in Human. CNVRs distribution in both species was more in subtelomeric and pericentromeric regions. According to these results, it could be possible to use bovine CNVRs which were closely linked to genes for characterizing functional genes and QTLs in sheep, however more studies are need in this regards.