Comparison of PFGE, IS6110-RFLP, and 24-Locus MIRU-VNTR for Molecular Epidemiologic Typing of Mycobacterium tuberculosis Isolates with Known Epidemic Connections

Abstract

Two molecular epidemiologic methods, IS restriction fragment length polymorphism (IS-RFLP) and 24-locus mycobacterial interspersed repetitive unit-variable-number tandem repeat (MIRU-VNTR), are used worldwide in studies of (MTB). Conversely, because of its poor resolution, pulsed-field gel electrophoresis (PFGE) is not widely used for MTB. In this study, we improved the 24-locus MIRU-VNTR and PFGE protocols and compared the effectiveness of these approaches for the molecular typing of MTB using 75 clinical isolates obtained from a cohort investigation of high-risk populations infected with MTB. The 24-locus MIRU-VNTR method demonstrated superior discriminatory ability, followed by PFGE and IS-RFLP. Next, we analyzed six isolates with clear epidemiologic connections; that is, isolates from patients who attended the same school. IS-RFLP and PFGE identified these samples as the same type. By contrast, according to MIRU-VNTR, two isolates differed from four other isolates at one locus each; one isolate was identified as Mtub29 and the other as QUB-26. In summary, the 24-locus MIRU-VNTR assay was the most useful molecular typing method among the three methods investigated due to its discriminatory power, short time required, and availability as an epidemiologic investigation tool. PFGE was the second-best method. Compared with the other loci assessed in the 24-locus MIRU-VNTR assay, the Mtub29 and QUB-26 loci appeared to exhibit greater variability during transmission.

A tuberculosis school outbreak in China, 2018: reaching an often overlooked adolescent population

“…MIRU-VNTR has a high utilisation value for the molecular epidemiology classification of M. tuberculosis with known epidemiological association, and it shows superior discrimination ability [23]. There are many studies on the molecular epidemiological investigation of MIRU-VNTR for tuberculosis [18, 24, 25].…”

Transmission of multidrug-resistant tuberculosis within family households by DTM-PCR and MIRU-VNTR genotyping

“…If defined as clusters within one locus, intra-family transmission increased to eighteen cases (81.8%), which was basically consistent with the results of family transmission of tuberculosis reported by Augustynowicz-Kopec et al [ 24 ]. As MIRU-VNTR assays discriminate genotypic differences during the transmission process, some loci may be variable during transmission [ 25 ]. Cavany SM's genotype among matched tuberculosis close contacts was 79% homologous, which also suggested higher contact transmission [ 26 ].…”

Code and data on the processing of the pulsed-field gel electrophoresis images: A matlab script

“…The data consist of several MATLAB codes, which collectively have the task of lane tracking, band detecting and pattern recognition on the pulsed-field gel electrophoresis images. The PFGE is a laboratory technique used by researchers and scientists to produce a DNA fingerprint for a bacterial isolate as a group of the same type of bacteria [[2], [3], [4], [5]]. The images were provided by two types of bacteria, including Acinetobacter [6], Staphylococcus aureus [7] which were attached with the article.…”