Evaluation of MIRU-VNTR for typing of Mycobacterium bovis isolated from Sika deer in Northeast China

Li Yang,Haijun Wang,Qingfeng Meng,Quankai Wang,Chunyu Wang

doi:10.1186/s12917-015-0402-0

Abstract

BackgroundBovine tuberculosis has led to serious economic losses for Sika Deer producers in China. Strategies for controlling the spread of Mycobacterium bovis are often hampered by a lack of epidemiological data. Specifically, tracing infections requires the ability to trace back infections, which, in turn, requires the ability to determine isolates with a common source. This study was planned to assess the discriminatory power of each mycobacterial interspersed repetitive unit (MIRU)-variable number tandem repeats (VNTR) locus and evaluate the most appropriate combination of MIRU-VNTR loci for molecular epidemiological studies on Sika Deer in China.ResultsThe discriminatory power of MIRU-VNTR typing based on 22 known loci (12 MIRUs, 2 ETRs, 4 QUBs, and 4 Mtubs) were assessed in 96 Mycobacterium bovis strains collected sequentially from Sika Deer at a slaughterhouse in northeastern China. We defined four loci (MIRU4, ETRA, QUB11b, and Mtub4) as highly discriminative, eight loci (MIRU2, MIRU23, MIRU27, MIRU31, MIRU39, MIRU40, QUB26, and Mtub21) as moderately discriminative, and three loci (MIRU16, Mtub30, and Mtub34) as poorly discriminative. The final locus showed no polymorphism between strains. MIRU-VNTR typing as a whole was highly discriminative, with an overall allelic diversity of 0.897. Of the loci tested, the four highly discriminative loci and eight moderately discriminative loci proved to be most appropriate for first line typing of M. bovis from Sika Deer, with the same resolving ability as all 22 loci (H = 0.897).ConclusionsMIRU-VNTR typing is quick and effective for typing bovine tuberculosis isolates from Sika Deer in China.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-015-0402-0) contains supplementary material, which is available to authorized users.

Highlights

Bovine tuberculosis has led to serious economic losses for Sika Deer producers in China
Sika Deer tuberculosis is caused by the Mycobacterium tuberculosis complex (MTBC); most commonly, M
mycobacterial interspersed repetitive unit (MIRU)-variable number tandem repeats (VNTR) has high efficiency and reproducibility, because MIRU-VNTR typing results are easier to compare between different laboratories than restriction fragment length polymorphisms (RFLP), which were the previous “gold standard” for MTBC typing [4]

Summary

Introduction

Bovine tuberculosis has led to serious economic losses for Sika Deer producers in China. Strategies for controlling the spread of Mycobacterium bovis are often hampered by a lack of epidemiological data. Previous efforts in controlling MTBC have been hampered by a lack of data, as genotyping MTBC members is an important tool in epidemiological analysis for studying the spread of MTBC [1]. MIRU-VNTR has high efficiency and reproducibility, because MIRU-VNTR typing results are easier to compare between different laboratories than restriction fragment length polymorphisms (RFLP), which were the previous “gold standard” for MTBC typing [4]. Another advantage of MIRU-VNTR is that it does not require large quantities of template DNA for typing [5]

Results

Discussion

Conclusion