Genetic structure and hybridization between red and sika deer in northern Italy

Since 2004-2005, events of introgression and hybridization have been reported among red deer (Cervus elaphus) and the sika deer (C. nippon) in Northern Italy. Aim of thes study was to assess the genetic structure and hybrid- ization between these two species. The genomic DNA from 71 legally hunted animals were genotyped using the ddRAD-seq technology. A medium-density SNP genotypes panel with about 8K markers was obtained. Genetic relationships, multidimensional scaling and Admixture revealed a notable degree of admixture, indicating that hybridization was occurring between sika and red deer. These findings underscore the complex dynamics of intro- gression and gene flow between these two species. Hybridization can have a large effect on the genetic structure of native populations, therefore understanding admixture patterns is vital for conservation to safeguard the genetic integrity of these species.