Search for genetic markers associated with susceptibility to mesiodens formation

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K10413
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 57070:Developmental dentistry-related
• Research Institution: Nihon University
• Principal Investigator: SHIMIZU Takehiko 日本大学, 松戸歯学部, 教授 (40328761)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 上顎正中過剰歯 / 遺伝子マーカー / 遺伝要因 / 一塩基多型

Outline of Final Research Achievements

A mesiodens is the most common supernumerary tooth present in the maxillary incisor area. There have been many reports regarding the prevalence and treatment for supernumerary teeth; however, the etiology of the condition is still unknown. This study aimed to identify genetic markers associated with susceptibility to mesiodens formation. The study population comprised 24 patients with mesiodens and 24 controls. Genomic DNA was obtained from the soft tissue of extracted supernumerary teeth or saliva samples. Genotypes and allele frequencies of single nucleotide polymorphisms (SNPs) in genes associated with supernumerary incisor formation in rodents, including SOSTDC1, LRP4 and PAX6 were compared between mesiodens group and controls using chi-squared tests. No positive polymorphisms were found in the tested SNPs between the two groups. However,rs6485702 which is one of the exon SNPs in LRP4 was detected with suggestive difference between the two groups.

Free Research Field

小児歯科学

Academic Significance and Societal Importance of the Research Achievements

上顎正中過剰歯が原因となり、永久前歯の位置異常や萌出障害を生じ、歯列不正が重篤化することがある。従って、小児の健全な歯列発育を誘導する上で、上顎正中過剰歯の早期発見、治療が重要となる。本研究において、上顎正中過剰歯群とコントロール群間で、LRP4遺伝子のエクソン内のrs6485702の遺伝子型・アレル頻度において示唆的な差が認められた。LRP4遺伝子の上顎正中過剰歯発症への関与の可能性を示唆する結果であり、今後同遺伝子のさらなる分析の必要性を示すものであった。本研究の成果は、今後上顎正中過剰歯発症に関わる遺伝子マーカーの検出に繋がる可能性があり、歯科臨床に大きく貢献できる可能性が示唆された。