Genetic History of Sheep Domestication

Abstract

Domestication of sheep in the Fertile Crescent region of the Near East is an important evolutionary and historical event. Modern DNA analysis of sheep remains can complement knowledge obtained through morphological analysis at archaeological sites. In particular, investigation of mitochondrial DNA and endogenous retroviral sequences are widely used for studying the domestication, migration, and origin of domestic sheep. Comparison of the mitochondrial genomes of wild and modern sheep has further facilitated investigations on the origin of domestic sheep, indicating that the mouflon (Ovis orientalis) is the ancestor of domesticated sheep. To date, five phylogenetically divergent lineages of mitochondrial DNA have been identified in domestic sheep. Migration events from the center of domestication were studied in detail using retroviral integration. This progress highlights the need to conduct further genetic studies of modern and ancient samples of sheep so as to gain a more in-depth understanding of domestication events, migration processes, and the formation of basic breeds of domestic sheep.