Quantitative evaluation for selection of optimal hard tissue for forensic DNA analysis

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K10552
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 58040:Forensics medicine-related
• Research Institution: Shinshu University
• Principal Investigator: Asamura Hideki 信州大学, 学術研究院医学系, 教授 (80324250)
• Co-Investigator(Kenkyū-buntansha): 佐藤 紀子 信州大学, 医学部, 助手(特定雇用) (00649254) ; 塩崎 哲也 信州大学, 医学部, 助教(特定雇用) (00722018) ; 小林 寛也 信州大学, 学術研究院医学系, 助教 (00826886)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: DNA多型 / 硬組織 / 劣化DNA試料 / DNA抽出 / DNA収量

Outline of Final Research Achievements

Experiments were conducted to determine which regions of the most challenging hard tissue samples for DNA analysis exhibit both good DNA preservation and high DNA recovery. DNA extraction was performed from a total of 16 sites from three individuals, and the samples were categorized into four groups: phalangeal and toe bones, long bones including the femur, tooth, and others. The STR typing success rate and DNA recovery were compared among these four groups. The findings consistently indicated a prominent pattern of high STR typing success rates and DNA recovery in phalangeal and toe bones. Therefore, it was suggested that phalangeal and toe bones, which demonstrate stable STR typing success rates and high DNA recovery, can serve as samples with good preservation and high DNA recovery in the field of forensic medicine.

Free Research Field

法医学

Academic Significance and Societal Importance of the Research Achievements

DNA鑑定技術が飛躍的に進歩しているにも関わらず硬組織を用いたDNA解析では多くの課題が残されている。DNA鑑定が最も困難な硬組織試料について、どの部位がDNAの保存状態が良好で且つDNA回収量が多いかについて科学的な根拠を得るべく研究を行った。これまでは単に大腿骨からのDNA検出率が良いとの科学的根拠のないままDNA検査が行われてきたが、我々の研究の結果、大腿骨よりも指骨といった骨梁構造が豊富な骨のほうが安定したDNA結果を得られることが明らかとなった。今後のDNA鑑定実務においてDNA検出率の安定した硬組織試料を選択することは法医実務にとって有用である。