Progress and discussion in molecular epidemiology of tuberculosis

Abstract

Molecular epidemiology of tuberculosis has a good prospect in tuberculosis control,and developed countries have applied it in the routine examination.In our country,there will be much greater application prospects and space.The current genotyping mainstream mode is common application of variable number tandem repears (VNTR) and spoligotyping.Spoligotyping is one of the most widely used methods applied to Mycobacterium tuberculosis genotyping after IS6110-restriction fragment length polymorphism (RFLP) method occurred and is used as a standard method for identification of Beijing genotype strains.VNTR method is simple,fast,low cost,repeatable,and easily compared between different laboratories.The VNTR loci selected in different countries and regions are different,different VNTR locus has different discriminatory index and the level needs further study.IS6110 RFLP method is no longer widely used,but it has been regarded as a gold standard for the identification of the accuracy of other genotyping methods.With the gradual progress of molecular biology techniques,some new trends emerge in genotyping technology.Large sequence polymorphism (LSP) and single nucleotide polymorphism (SNP) are two of the high frequency genotyping methods emerged in recent years.Although the discriminationary index of LSP and SNP is not high,they can be used for the research of phyletic evolution.Phylogenetics research begins from the application of VNTR 15 and VNTR-24 methods,however,people found that the presence of uncertainty and error was relatively large.Following the more complete understanding of the characteristics of LSP and SNP,it is believed that LSP and SNP are the best methods for phylogenetics research.With the advances in molecular biology technology,molecular epidemiology of tuberculosis will provide more supports and guidance for the prevention and control of tuberculosis. Key words: Genotyping; Variable number tandem repeats; Spoligotyping; Phylogenetics