摘要
Objective We determined the genetic diversity of Mycobacterium tuberculosis(MTB) in a remote mountainous area of southwest China and evaluated the resolving ability of single nucleotide polymorphism(SNP) genotyping combined with variable number tandem repeat(VNTR) genotyping for Beijing family strains in association with drug resistance status.Methods Three hundred thirty-one MTB strains were isolated from patients living in mountainous regions of southwest China,and 8-loci SNP,VNTR-15 genotyping assays,and drug susceptibility testing of 9 drugs were performed.Results A total of 183 [55.29%(183/331)] strains were classified into the Beijing family.Of the 183 strains,111(60.66%) were defined as modern Beijing strains.The most predominant modern Beijing sub-lineage and ancient Beijing sub-lineage were Bmyc10 [39.34%(72/183)] and Bmyc25 [20.77%(38/183)],respectively.Of the isolates,19.64%(65/331) were resistant to at least 1 of the 9 anti-TB drugs and 17 [4.98%(17/331)] MTB isolates were multi-drug resistant tuberculosis(MDR-TB).Two hundred sixty-one isolates showed a clustering rate of 14.18%(37/261) and a discriminatory index of 0.9990.The Beijing lineage exhibited a significantly higher prevalence of MDR-TB,as well as resistance to isoniazid(INH),rifampin(RIF),and para-aminosalicylic acid(PAS) when analyzed independently(P = 0.005,P = 0.017,P = 0.014,and P = 0.006 respectively).The Beijing lineage was not associated with genetic clustering or resistance to any drug.In addition,genetic clustering was not associated with drug resistance.Conclusion MTB strains demonstrate high genetic diversity in remote mountainous areas of southwest China.Beijing strains,especially modern Beijing strains,are predominant in remote mountainous area of China.The combination of 8-loci SNPs and VNTR-15 genotyping is a useful tool to study the molecular epidemiology of MTB strains in this area.
Objective We determined the genetic diversity of Mycobacterium tuberculosis(MTB) in a remote mountainous area of southwest China and evaluated the resolving ability of single nucleotide polymorphism(SNP) genotyping combined with variable number tandem repeat(VNTR) genotyping for Beijing family strains in association with drug resistance status.Methods Three hundred thirty-one MTB strains were isolated from patients living in mountainous regions of southwest China,and 8-loci SNP,VNTR-15 genotyping assays,and drug susceptibility testing of 9 drugs were performed.Results A total of 183 [55.29%(183/331)] strains were classified into the Beijing family.Of the 183 strains,111(60.66%) were defined as modern Beijing strains.The most predominant modern Beijing sub-lineage and ancient Beijing sub-lineage were Bmyc10 [39.34%(72/183)] and Bmyc25 [20.77%(38/183)],respectively.Of the isolates,19.64%(65/331) were resistant to at least 1 of the 9 anti-TB drugs and 17 [4.98%(17/331)] MTB isolates were multi-drug resistant tuberculosis(MDR-TB).Two hundred sixty-one isolates showed a clustering rate of 14.18%(37/261) and a discriminatory index of 0.9990.The Beijing lineage exhibited a significantly higher prevalence of MDR-TB,as well as resistance to isoniazid(INH),rifampin(RIF),and para-aminosalicylic acid(PAS) when analyzed independently(P = 0.005,P = 0.017,P = 0.014,and P = 0.006 respectively).The Beijing lineage was not associated with genetic clustering or resistance to any drug.In addition,genetic clustering was not associated with drug resistance.Conclusion MTB strains demonstrate high genetic diversity in remote mountainous areas of southwest China.Beijing strains,especially modern Beijing strains,are predominant in remote mountainous area of China.The combination of 8-loci SNPs and VNTR-15 genotyping is a useful tool to study the molecular epidemiology of MTB strains in this area.
作者
ma ai jing
wang sheng fen
fan jia le
zhao bing
he guang xue
zhao yan lin
MA Ai Jing;WANG Sheng Fen;FAN Jia Le;ZHAO Bing;HE Guang Xue;ZHAO Yan Lin(National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China;National Center for TB Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China;Science and Technology Department, Chinese Center for Disease Control and Prevention, Beijing 102206, China)
基金
supported by the National Science and Technology Major Project 2014ZX100030002
The National Basic Research Program of China 2014CB744403