Whole Genome Analysis Reveals Ancient Japanese Kinship Structure: Burial Tombs of the Kofun Period

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K15885
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 45050:Physical anthropology-related
• Research Institution: National Museum of Nature and Science, Tokyo
• Principal Investigator: Kanzawa Hideaki 独立行政法人国立科学博物館, 人類研究部, 研究主幹 (80734912)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 古代DNA / 古墳時代 / 血縁推定 / 核ゲノム / ミトコンドリアゲノム / Y染色体 / 埋葬原理

Outline of Final Research Achievements

The study has focused on the Suwadani site in Kisarazu City, Chiba Prefecture, where the quality of human remains are preferable for DNA analysis. Mitochondrial and nuclear genome analysis were conducted on 14 human remains to investigate the genetic background of the buried individuals and kinship relationships within and between the burial graves. Mitochondrial genomes were determined from 13 individuals, and Several haplogroups were shared among individuals, which may indicate consanguinity in the maternal lineage. Next, nine of the individuals that were determined to be suitable for nuclear genome analysis were subjected to large-scale sequencing using a next-generation sequencer HiSeq X, and related pairs were detected based on the nuclear genomes as well. The genetic characteristics of the individuals were confirmed to be within the category of modern Japanese and not significantly different from those of other Kofun period people in the Kanto region.

Free Research Field

分子人類学

Academic Significance and Societal Importance of the Research Achievements

従来の古墳時代の埋葬人骨の親族研究を行う際には、人骨の歯冠計測値に基づく形態学的な分析がこれまで行われてきたが、その信頼性には疑問が呈され、他人の空似を排除できない問題があった。近年のDNA分析の進展により、ミトコンドリアDNA分析による母系系統での血縁関係が明らかにされるようになったが、父系系統が不明な点や何親等なのかを明らかにすることができないなど、課題もあった。本研究では埋葬人骨の全ゲノム解析を行うことによって、母系系統のミトコンドリアDNAだけでなく、男系系統のY染色体、両系統の核ゲノムを用いた精度の高い血縁推定を試みた点で、これまでの古墳時代の親族研究を進展させる成果となった。