scholarly journals Typing Method for the QUB11a Locus ofMycobacterium tuberculosis: IS6110Insertions and Tandem Repeat Analysis

2016 ◽  
Vol 2016 ◽  
pp. 1-6
Author(s):  
Eriko Maeda-Mitani ◽  
Koichi Murakami ◽  
Akira Oishi ◽  
Yoshiki Etoh ◽  
Nobuyuki Sera ◽  
...  

QUB11a is used as a locus for variable number of tandem repeats (VNTR) analysis ofMycobacterium tuberculosisBeijing lineage. However, amplification of QUB11a occasionally produces large fragments (>1,400 bp) that are not easily measured by capillary electrophoresis because of a lack of the typical stutter peak patterns that are used for counting repeat numbers. IS6110insertion may complicate VNTR analysis of large QUB11a fragments inM. tuberculosis. We established a method for determining both tandem repeat numbers and IS6110insertion in the QUB11a locus ofM. tuberculosisusing capillary electrophoresis analysis andBsmBI digestion. All 29 large QUB11a fragments (>1,200 bp) investigated contained IS6110insertions and varied in the number of repeats (18 patterns) and location of IS6110insertions. This method allows VNTR analysis with high discrimination.

2017 ◽  
Vol 56 (1) ◽  
Author(s):  
Yoshiro Murase ◽  
Kiyohiko Izumi ◽  
Akihiro Ohkado ◽  
Akio Aono ◽  
Kinuyo Chikamatsu ◽  
...  

ABSTRACT Strain genotyping based on the variable-number tandem repeat (VNTR) is widely applied for identifying the transmission of Mycobacterium tuberculosis. A consensus set of four hypervariable loci (1982, 3232, 3820, and 4120) has been proposed to improve the discrimination of Beijing lineage strains. Herein, we evaluated the utility of these four hypervariable loci for tracing local tuberculosis transmission in 981 cases over a 14-month period in Japan (2010 to 2011). We used six different VNTR systems, with or without the four hypervariable loci. Patient ages and weighted standard distances (a measure of the dispersion of genotype-clustered cases) were used as proxies for estimating local tuberculosis transmission. The highest levels of isolate discrimination were achieved with VNTR systems that incorporated the four hypervariable loci (i.e., the Japan Anti-Tuberculosis Association [JATA]18-VNTR, mycobacterial interspersed repetitive unit [MIRU]28-VNTR, and 24Beijing-VNTR). The clustering rates by JATA12-VNTR, MIRU15-VNTR, JATA15-VNTR, JATA18-VNTR, MIRU28-VNTR, and 24Beijing-VNTR systems were 52.2%, 51.0%, 39.0%, 24.1%, 23.1%, and 22.0%, respectively. As the discriminative power increased, the median weighted standard distances of the clusters tended to decrease (from 311 to 80 km, P < 0.001, Jonckheere-Terpstra trend test). Concurrently, the median ages of patients in the clusters tended to decrease (from 68 to 60 years, P < 0.001, Jonckheere-Terpstra trend test). These findings suggest that strain typing using the four hypervariable loci improves the prediction of active local tuberculosis transmission. The four-locus set can therefore contribute to the targeted control of tuberculosis in settings with high prevalence of Beijing lineage strains.


2007 ◽  
Vol 56 (8) ◽  
pp. 1052-1057 ◽  
Author(s):  
Takayuki Wada ◽  
Shinji Maeda ◽  
Atsushi Hase ◽  
Kazuo Kobayashi

Using 243 Mycobacterium tuberculosis isolates obtained in 2001 in Osaka City, Japan, the discriminatory power of variable numbers of tandem repeats (VNTRs) of 12 standard mycobacterial interspersed repetitive units (MIRUs) was assessed. The biggest cluster defined by MIRU-VNTRs consisted of 57 (23.5 %) isolates and they belonged to the Beijing family based on spoligotyping. When additional VNTR loci were included in the MIRU-VNTR analysis, the 57 originally clustered strains were further differentiated by the addition of Queen's University Belfast (QUB)-VNTRs, but not exact tandem repeat-VNTR. The allelic diversity of additional VNTR loci such as VNTR 3232 (QUB-3232), VNTR 2163a (QUB-11a), VNTR 2163b (QUB-11b) and VNTR 1982 (QUB-18) was high in the 57 strains. When the 243 M. tuberculosis isolates were analysed using 16-locus VNTR (the 12 standard MIRUs and the 4 QUB loci) and IS6110 RFLP, the respective Hunter–Gaston discriminatory indexes were 0.9966 and 0.9971. The discrimination power of 16-locus VNTR was equal to that of IS6110 RFLP analysis. If appropriate loci are added to the standard MIRU analysis, VNTR genotyping could be a valuable tool for strain typing and epidemiological research of M. tuberculosis in Japan.


2017 ◽  
Vol 22 (9) ◽  
Author(s):  
Tansy Peters ◽  
Sophie Bertrand ◽  
Jonas T Björkman ◽  
Lin T Brandal ◽  
Derek J Brown ◽  
...  

Multilocus variable-number tandem repeat analysis (MLVA) is a rapid and reproducible typing method that is an important tool for investigation, as well as detection, of national and multinational outbreaks of a range of food-borne pathogens. Salmonella enterica serovar Enteritidis is the most common Salmonella serovar associated with human salmonellosis in the European Union/European Economic Area and North America. Fourteen laboratories from 13 countries in Europe and North America participated in a validation study for MLVA of S. Enteritidis targeting five loci. Following normalisation of fragment sizes using a set of reference strains, a blinded set of 24 strains with known allele sizes was analysed by each participant. The S. Enteritidis 5-loci MLVA protocol was shown to produce internationally comparable results as more than 90% of the participants reported less than 5% discrepant MLVA profiles. All 14 participating laboratories performed well, even those where experience with this typing method was limited. The raw fragment length data were consistent throughout, and the inter-laboratory validation helped to standardise the conversion of raw data to repeat numbers with at least two countries updating their internal procedures. However, differences in assigned MLVA profiles remain between well-established protocols and should be taken into account when exchanging data.


2015 ◽  
Vol 64 (5) ◽  
pp. 507-512 ◽  
Author(s):  
Camila Hamond ◽  
Melissa Pinna ◽  
Marco Alberto Medeiros ◽  
Pascale Bourhy ◽  
Walter Lilenbaum ◽  
...  

2008 ◽  
Vol 73 (2) ◽  
pp. 111-117 ◽  
Author(s):  
Alexander J. Nederbragt ◽  
Anusha Balasingham ◽  
Reidun Sirevåg ◽  
Hans Utkilen ◽  
Kjetill S. Jakobsen ◽  
...  

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