2023 Fiscal Year Final Research Report

Evaluation of epigenetic aging changes in hard tissues and its application on age estimation

Research Project

PDF

Project/Area Number	21K10253
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 57080:Social dentistry-related
Research Institution	Hiroshima University
Principal Investigator	Oka Hiroko 広島大学, 医系科学研究科(歯), 主任特任学術研究員 (60452588)
Co-Investigator(Kenkyū-buntansha)	北川雅恵広島大学, 病院(歯), 助教 (10403627) 宮内睦美広島大学, 医系科学研究科(歯), 教授 (50169265) 加藤文紀広島大学, 医系科学研究科(歯), 助教 (70452589)
Project Period (FY)	2021-04-01 – 2024-03-31
Keywords	硬組織 / メチル化 / 年齢推定 / 歯
Outline of Final Research Achievements	This study aimed to explore DNA methylation targets associated with calcification of hard tissue constituent cells and verify their association with chronological age in real hard tissue. In addition, the study aimed to develop novel age estimation methods from hard tissue using real-time PCR. Using a cementoblast like cell line, we showed that proliferation and differentiation of the cementoblast like cells were regulated various DNA methylation targets. In extracted tooth specimens, there are positive correlation between a DNA methylation targets and chronological age. A regression equation was obtained using age as the objective variable, and the presence or absence of alveolar bone resorption (morphological index) and the extracted methylation targets (biochemical index) as the explanatory variable. The equations obtained were not influenced by lifestyle habits (smoking, daily coffee consumption).
Free Research Field	法歯学、社会歯学
Academic Significance and Societal Importance of the Research Achievements	歯根周囲から得た微量なDNAから、リアルタイムPCRを用いて得られるFHL2メチル化スコアを年齢推定への応用の可能性が示された。また、今回ターゲットとした歯根周囲のDNAメチル化部位は喫煙やコーヒーの日常摂取の影響を受けていないことが明らかとなった。身元不明の腐敗遺体や白骨であっても、顎骨に植立された状態であれば分析対象となる歯を支持する歯槽骨吸収の程度もエックス線撮影や肉眼で非破壊的に評価可能である。微量の試料採取と非破壊的検査による本研究のアプローチは、遺族感情に寄り添い資料保存も可能となる年齢推定法への展開に大きく寄与するものと考えられた。