The Three Kingdoms period is a turning point in Korean history. It was at this time, between the 4th and 7th centuries, that the foundations of a common cultural heritage were laid as Buddhism rapidly became the official religion in the kingdoms of Korio, Baekje and Silla.
The genetic history of these prehistoric Korean populations, however, has never been thoroughly investigated because only a small number of ancient genomes existed. The genomes of up to eight people who lived about 1,700 years ago and who were buried at two sites in the city of Gimhae, South Korea, have now been sequenced: the Yuha-ri shell mound and the Daesung-dong burial mounds, the complex most important funerary of the Gaya confederation (absorbed by Silla in the first half of the 6th century).
The results are very clear. All of these individuals show admixture between a genetic source from northern China of the Bronze Age and another related to the Jomon period of Japan (beginning around 14,500 BC and ending around 300 BC), similar to the current Japanese genomes.
"This means that in the past, the Korean peninsula showed more genetic diversity than in our times," says Pere Gelabert, a researcher at the University of Vienna and lead author of the paper published in the journal Current Biology.
Baekje was, in the fourth century, a very prosperous state that dominated the south of the Korean peninsula. It was the only one that maintained foreign relations with Japan, receiving its influence in architecture, art and literature. Koguryo, the largest of the three kingdoms, bordered China and gradually conquered vast territories in Manchuria.
Some of the individuals studied were tomb owners, others were human sacrifices, and the last, a child, was buried in a shell mound, a typical Southeast Asian funerary monument unrelated to the privileged. All burial sites are typical of the funerary practices of the Gaya region between AD 300 and 500.
"Individual genetic differences are not correlated with tomb typology, indicating that social status in Three Kingdoms Korea would not be linked to genetic ancestry. We have observed that there is no clear genetic difference between tomb owners." tombs and human sacrifices“, explains Gelabert.
Six of these eight individuals were genetically closer to modern Koreans, modern Japanese, Kofun Japanese (the period of Japanese history from 250 to 538), and Neolithic Koreans. The genomes of the remaining two were slightly closer to Jomons and modern Japanese.
Modern Koreans, however, seem to have lost this genetic component related to the Jomon period due to relative isolation following the Three Kingdoms period, when Silla conquered Baekje in 660 and Koguryo in 668 in alliance with the Chinese Tang dynasty. .
"These results support a well-documented post-Three Kingdoms history, suggesting that Koreans of that time intermingled within the peninsula and their genetic differences diminished until the Korean population became homogeneous as we know it today." , explain the researchers.
A detailed prediction of facial features based on DNA from all eight genomes showed that Koreans of the Three Kingdoms period resembled modern Koreans in their hair and eye color, facial morphology, and myopia.
