Molecular characterization of embB306 gene in Mycobacterium tuberculosis isolates from tuberculosis patients in Chongqing municipality.
- Author:
Hui LIN
1
;
Jie LIU
;
Lin CHEN
;
Kuan-he JING
;
Jing SHEN
;
Jian ZHAN
;
Ya-fei LI
;
Ru-fu XU
;
Hong-yan XIONG
;
Jia CAO
Author Information
- Publication Type:Journal Article
- MeSH: China; DNA Mutational Analysis; DNA, Bacterial; genetics; Genes, Bacterial; Humans; Mutation; Mycobacterium tuberculosis; drug effects; genetics; isolation & purification; Pentosyltransferases; genetics; Tuberculosis, Multidrug-Resistant; microbiology
- From: Chinese Journal of Preventive Medicine 2009;43(3):223-226
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo understand the characteristics of embB gene mutation of Mycobacterium tuberculosis (MTB) isolates from tuberculosis patients in Chongqing, and the value of embB306 as a molecular marker used to diagnose ethambutol (EMB)-resistant MTB strains.
METHODSDirect sequencing was used to analyze the polymorphism of embB mutation in 51 EMB-resistant MTB strains and 50 EMB-sensitive MTB strains. And diagnostic testing was used to evaluate the value of embB306 as a molecular marker of EMB -resistant MTB strains as compared with the traditional sensitivity test.
RESULTSAll 34 of 51 EMB-resistant strains (66.7%) and 3 of 51 EMB-sensitive strains (6%) had had embB306 mutation. The embB306 mutation rate in EMB-resistant strains coming from previously treated case was 87.5%, showing significantly higher than that from new cases (48.1%, P < 0.01); embB306 mutation rate was increased with the number of the resistant drugs; embB306 mutation serving as a marker to diagnose EMB-resistant MTB strains comparing with the traditional sensitivity test, had the rate of sensitivity = 66.7%, specificity = 94.0%, accuracy = 80.2% and Youden index = 60.7%.
CONCLUSIONembB306 mutation should be the main mechanism of MTB resistance to EMB in Chongqing, showing an association with the history of the treated and numbers of the resistant drugs. embB306 mutation should be a good marker to diagnose EMB-resistant MTB strains.
