Investigating the origins of the eastern Eurasian sheep using Xiongnu-period ancient sheep genomes from Mongolia ; 흉노 시기 몽골 양 유전체를 통한 동아시아 양의 유전적 기원 연구

학위논문(석사) -- 서울대학교대학원 : 자연과학대학 생명과학부, 2022. 8. 정충원. ; Sheep (Ovis aries) is one of the earliest animals domesticated by humans about 10,000 to 12,000 years ago in Southwestern Asia when human subsistence patterns drastically transformed from a hunter-gatherer to a sedentary lifestyle. Sheep have dispersed through human activities and have been well adapted around the world. Especially, domestic sheep have become essential livestock in the Mongolian grasslands as a stable source of nutrition and hydration, where crop cultivation faces challenges and nomadic pastoralism is commonly practiced. However, the evolutionary history of domestic sheep in East Asia and its associated pastoralist societies are poorly understood. In this study, to explore the origins of present-day sheep in eastern Eurasia (i.e., East Asia), the first whole-genome data of ancient sheep from the Mongolian grasslands are presented. Duurlig Nars is one of the funeral sites of Xiongnu elite, nomadic pastoralist people who played an important role in cultural exchanges between the West and the East. Genome-wide data of six individuals from the satellite burials of Duurlig Nars tomb, along with previously published 11 ancient individuals, and 514 present-day individuals were generated using the 7497K SNPs identified in this study and population genetic analyses were conducted. Results indicate the strong genetic affinity between Xiongnu-period Duurlig Nars sheep and the present-day East Asian populations. Other ancient sheep populations also show a high genetic affinity with the present-day populations geographically close to their excavation site. Also, a combined analysis of genome-wide data and mitochondrial DNA on ancient populations suggest ancestry continuity. In conclusion, this study reports the first whole-genome data of ancient East Asian sheep and confirms that the complex genetic structure in present-day sheep formed at least 2,000 years ago. Moreover, the worldwide sheep diversity panel of 7497K SNPs identified in this study will ...