The Nubian ibex

The Nubian ibex

The Nubian ibex (Capra nubiana) is a wild goat species that inhabits the Sahara and Arabian deserts characterized by extreme ambient temperatures, intense solar radiation, and scarcity of food and water resources. To investigate desert adaptation, we explored the role of copy number variations in the evolution of Capra species, focusing specifically on the environment of C. nubiana. Copy number variations (CNVs) are structural genomic variations that have been implicated in phenotypic differences between species and could play a role in species adaptation. C. nubiana genome was sequenced to an average read depth of 37x. Combinations of read-depth and split-read approaches were used to predict CNVs in C. nubiana genome relative to the reference domestic goat genome. A total of 1,624 CNVs loci were identified; 243 of the CNVs overlapped with protein-coding genes mainly involved in immune response, olfactory transduction, and general metabolism processes. The immune response genes such as Natural Killer Group 2D ligands and Type 1 Interferon were the most variable, possibly suggesting their roles in C. nubiana adaptations to viral infections. The results provide new insights into the genetic basis of C. nubiana adaptation to its environment and genomic resources that will speed up CNV association studies of important traits in Capra species.