Molecular analysis of isoniazid-resistant Mycobacterium tuberculosis

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K07121
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 49050:Bacteriology-related
• Research Institution: Juntendo University
• Principal Investigator: Kirikae Teruo 順天堂大学, 医学部, 教授 (50192563)
• Co-Investigator(Kenkyū-buntansha): 竹本 訓彦 国立研究開発法人国立国際医療研究センター, その他部局等, 上級研究員 (40546793)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 結核 / 薬剤耐性 / イソニアジド耐性 / 薬剤耐性遺伝子 / イソニアジド耐性遺伝子 / 中等度耐性 / 全ゲノム解析 / 系統樹解析

Outline of Final Research Achievements

Drug-resistant Mycobacterium tuberculosis isolates were obtained from 254 patients (202 Japan-born and 52 foreign-born) in Japan. The whole genome sequences and lineages of these isolates were determined and phylogenetic trees were constructed. Of the 254 isolates, 54 were multidrug-resistant. The percentages of multidrug-resistant isolates were significantly higher in foreign-born than Japan-born patients. Nine multidrug-resistant isolates were extensively drug-resistant and obtained from Japan-born patients. A significant number of multidrug-resistant M. tuberculosis strains were isolated from foreign-born patients. Foreign-derived isolates affect the nationwide genetic diversity of drug-resistant M. tuberculosis in Japan. Extensively drug-resistant M. tuberculosis isolates were transmitted among the Japanese population. This study was summarized in the following paper;
Mizukoshi F et al: Molecular Epidemiology of Drug-Resistant Mycobacterium Tuberculosis in Japan, mSphere, in press.

Free Research Field

微生物学

Academic Significance and Societal Importance of the Research Achievements

全国で分離された薬剤耐性結核菌の全ゲノム情報を解析し、その性状や分布、遺伝子系統、薬剤耐性に関与する遺伝子について解析した。これらの結果、日本人と外国人の患者由来薬剤耐性結核はそれぞれ異なる系統の分類を示した。外国人由来の多剤耐性結核菌の割合は日本人由来結核菌の割合より優位に大きかった。外国人由来薬剤耐性結核菌は日本全国の薬剤耐性結核の多様性に優位に影響していた。超多剤耐性結核は日本人の間で伝播していることが分かった。これらの基礎データは、日本における薬剤耐性結核対策の基礎資料を提供する。