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1.
目的评价不同串联重复序列(VNTR)位点在四川省结核分枝杆菌中的基因多态性,以及不同VNTR位点组合在四川省结核分枝杆菌基因分型中的应用。方法采用多位点数目可变串联重复序列分析技术(ML-VA)对102株四川省结核分枝杆菌菌株的15个VNTR位点进行分析,基因多态性分析采用Hunter-Gaston指数,聚类分析采用BioNumerics软件。结果 15个VNTR位点的基因多态性存在较大的差异,位点Mtub21(HGI 0.772)和MIRU26(HGI 0.764)的多态性较高,ETR-C(HGI 0.168)和MIRU23(HGI 0.077)的多态性较差。ETR-B和ETR-C两个位点在对四川省北京基因型结核分枝杆菌进行分型时则不具有多态性。对不同的VNTR位点组合进行比较,随着VNTR位点的增加,VNTR分型方法的分辨能力也有所提高。10个VNTR位点组合的分辨指数与15位点组合的分辨指数相差不大。同一VNTR位点在不同地区北京基因型菌株中的分辨力也存在较大的差异。结论不同VNTR位点在四川省结核分枝杆菌中具有不同的分辨力,并且同一VNTR位点在不同地区的北京家族菌株中的分辨力也不同。10个VNTR位点组合的基因分型方案可用于四川省结核分枝杆菌基因分型的一线方法。本研究的数据结果对挑选适合中国结核分枝杆菌基因分型的VNTR位点组合法具有重要的作用。  相似文献   

2.
天津地区临床分离结核分枝杆菌分型的初步研究   总被引:1,自引:0,他引:1  
目的探讨天津地区结核分枝杆菌临床分离株分子流行病学特征。方法连续收集天津市海河医院2005年8月16日11月25日就诊患者痰培养阳性的结核分枝杆菌100株,采用间隔区寡核苷酸分型(spoligotyping)和多位点可变串联重复序列(VNTR)两种方法进行基因分型,并运用软件对二者的结果进行分析。依据北京分化支的定义,运用多重和实时定量PCR方法将其区分为W菌/典型北京家族菌株和非典型北京菌株,Χ^2检验分析两种亚群与患者年龄和耐药性之间的联系。结果排除污染菌株,共对96株结核分枝杆菌临床分离株进行两种方法的基因分型,spoligotyping结果91.7%为北京基因型(含3株类北京基因型)结核分枝杆菌(88/96)。VNTR分型可将北京基因型分为60种基因型。在北京分化支结核分枝杆菌中,W菌/典型北京家族菌株占93.2%(82/88)。两种北京分化支亚群与患者年龄及耐药性之间差异无统计学意义(P〉0.05)。结论天津地区结核病患者临床分离的结核分枝杆菌中,北京基因型呈现较为明显的优势。VNTR的分辨率明显高于spoligotyping。北京分化支的两种亚群在天津地区临床结核病患者中均有流行,但以W菌/典型北京家族菌株为主。  相似文献   

3.
目的 初步评价不同串联重复序列(VNTR)位点在中国8省市结核分枝杆菌基因分型中的应用,寻找适合中国地区结核分枝杆菌基因分型的位点组合.方法 从中国8个省(市、自治区)2800余株结核分枝杆菌临床分离菌株中以简单数字表法随机抽取140株,采用多位点数目可变串联重复序列分析方法(MLVA)对27个数目可变VNTR位点进行基因多态性检测,采用BioNumerics数据库软件进行单位点和不同位点组合的分辨率(Hunter-Gaston指数,HGI)分析,并比较分析其对140株菌的基因分型鉴定能力.同时采用间隔区寡核苷酸分型(Spoligotyping)将140株菌分为北京家族和非北京家族,评价上述不同VNTR位点组合在北京家族和非北京家族中的分型能力.结果 140株菌主要可分为2个基因群,即北京家族112株,占80%;非北京家族28株,占20%.Spoligotyping分型对140株结核分枝杆菌的HGI为0.4589.MLVA分析结果显示不同位点在不同菌株群存在明显的多态性,不同位点的HGI具有较大差异(0~0.809),对全部菌株、北京家族菌株、非北京家族菌株的HGI达到0.5以上的VNTR位点数分别为8、7和14个.27个VNTR位点进行不同的位点组合:优化筛选的8位点组合、国际推荐的12个、15个和24个位点组合.4个组合的HGl分别为0.9991、0.9882、0.9980和0.9986;在北京家族菌株中,上述组合的HGI依次为0.9987、0.9318、0.9969和0.9975;在非北京家族菌株中分别为1、0.9894、1和1.结论不同的VNTR位点和不同VNTR位点组合在中国8省市结核分枝杆菌中的HGI均存在明显差异;本研究优化的8个位点组合MLVA分型方法在中国结核分枝杆菌流行病学研究可能具有良好的应用前景.  相似文献   

4.
目的 比较15位点分枝杆菌散在重复单元-可变数目串联重复序列(MIRU-VNTR)对河南省结核分枝杆菌的分辨力与其他地区的区别。方法 使用Spoligotyping和MIRU-VNTR对菌株进行分型,分析北京家族基因型在性别、年龄和地区间的分布情况。将15个位点对本省菌株的分辨率与其他地区结果相比较。结果 本省东部地区患者感染北京家族结核的比例高于其他地区,尤其高于西部地区。本省55岁以上的人群更易感染北京型菌株。7个位点(Mtub04、MIRU10、MIRU39、MIRU31、Mtub21、MIRU26和Qub26)对河南菌株的分辨能力优于其他地区。15位点MIRU-VNTR结合Spoligotyping的分辨力高于我国其他大部分地区,但略低于上海和黑龙江。结论 北京基因型在本省的分布存在地区和年龄的差异。15个位点MIRU-VNTR的分辨力在本省和其他地区间存在明显不同,因此需针对本省菌株指定合适的分型方案。  相似文献   

5.
目的运用可变数目串联重复(VNTR)分型方法研究农村结核病研究现场的结核分杆菌分离株的分子特征,分析与VNTR优势基因型相关的因素.方法经PCR扩增各分离株的5种确切串联重复位点(ETR-A~ETR-E).根据扩增产物大小,确定各串联重复单元的拷贝数,得出每个菌株的VNTR基因型.结果研究现场的101株菌株共分为37个不同的VNTR类型,22名病人分离株为单一基因型,79名病人的菌株分属于15个簇,VNTR42435类型占研究菌株总数的38.6%,但该基因型与卡介苗(BCG)接种耐4种一线药的相关性差异均无统计意学义.结论VNTR分型方法简单快速、分型结果数字化,可以把研究菌株分为不同的群.尚不能认为VNTR 42435的优势来自某些抗痨药和BCG接种.  相似文献   

6.
目的研究间隔区寡核苷酸序列基因分型技术、结核分枝杆菌散在分布重复单位(MIRU),以及多位点串联重复序列(VNTR)在河南省结核病分枝杆菌基因分型中的应用,了解河南省局部地区MIRU-VNTR基因型种类与分布,以及北京家族基因型在河南省的分布特征。方法应用2007年在河南省的嵩县、新密县、扶沟县、中牟县等4个县及南阳市的结核病防治机构实验室分离培养的344株结核分枝杆菌,设计引物,应用PCR和琼脂糖凝胶电泳技术及间隔区寡核苷酸分型技术对结核分枝杆菌进行VNTR分型检测分析,基因分型聚类分析采用Bio-Numerics软件。结果对344株结核分枝杆菌临床分离株的间隔区寡核苷酸分型结果显示,有299株为北京家族基因型,占86.9%;12个MIRU位点检测结果显示明显的基因多态性;经基因聚类分析,可分5个基因群(Ⅰ~Ⅴ群),292个基因型,Ⅰ~Ⅴ群分别占5.1%、67.8%、21.9%、1.4%、2.8%。结论河南省结核分枝杆菌MIRUs基因存在明显的多态性,存在≥5个MIRU型,主要流行型为Ⅱ型;北京家族基因型占主导地位,北京家族基因型与耐药无明显相关性。  相似文献   

7.
目的:探讨MIRU-VNTR技术在杭州地区结核分枝杆菌氧氟沙星耐药株基因分型中的应用。方法收集杭州市2010年4月-2012年6月各结核病定点医院分离培养的临床菌株,进行药物敏感性检测。分别采用RD105缺失基因检测法和MIRU-VNTR技术对氧氟沙星耐药株进行菌株鉴定和基因分型。结果筛选出的52株氧氟沙星耐药株中,43株(82.69%)为北京家族菌株。经12个MIRU-VNTR位点组合分析,52株氧氟沙星耐药株呈52种MIRU-VNTR基因型,总Hunter-Gaston指数( HGI)为0.999。除MIRU40和ETR-F外,其他10个MIRU-VNTR位点对北京家族菌株和非北京家族菌株均显示较高或中等程度的分辨率。结论筛选到的10个MIRU-VNTR位点具有较高分辨率,适用于杭州地区结核分枝杆菌氧氟沙星耐药株分型。  相似文献   

8.
目的利用脑膜炎奈瑟菌基因组中可变数目串联重复序列(VNTR)特征,对中国C群脑膜炎奈瑟菌菌株进行基因分型.方法中国C群脑膜炎奈瑟菌菌株109株,选择脑膜炎奈瑟菌DNA中4个VNTR位点,PCR扩增含有串联重复序列的DNA片段,选择每一个VNTR位点有差别的PCR产物进行测序,序列比对,测算串联重复序列的拷贝数.Bio-Rad Gel DocTM XR凝胶成像分析系统计算PCR产物DNA片段的碱基含量,换算成串联重复数;对109株菌株4个位点的串联重复序列拷贝数进行聚类分析,依据聚类分析结果进行基因分型,并将VNTR基因分型结果与脉冲场凝胶电泳基因分型(PFGE)结果进行比较.结果109株C群脑膜炎奈瑟菌菌株分为22个VNTR基因型,同一暴发来源的菌株具有相同VNTR特征;VNTR基因分型方法与PFGE基因分型具有相关关系.结论应用VNTR技术可以对中国C群脑膜炎奈瑟菌进行基因分型和分子流行病学方面的研究,VNTR基因分型可较好地应用于追溯流行性脑脊髓膜炎暴发传染源.  相似文献   

9.
目的初步探讨多位点数目可变串联重复序列(MLVA)技术在西藏地区结核分枝杆菌基因分型中的应用和初步了解西藏地区结核分枝杆菌数目可变串联重复序列(VNTR)基因型种类及其分布。方法在拉萨、山南、林芝、日喀则、那曲、昌都6个地区结核病防治中心收集结核分枝杆菌临床分离菌株,设计引物,采用PCR和琼脂糖凝胶电泳技术对结核分枝杆菌20个VNTR位点进行检测,并通过BioNumerics 4.5软件进行DNA指纹图谱多态性分析。结果共收集到217株结核分枝杆菌,分为19个不同的VNTR基因型,其中以Ⅺ型为主要基因型占87.6%(属于北京家族),其次Ⅵ型、ⅩⅤ型、ⅩⅥ型各占1.38%,Ⅰ型、Ⅶ型、ⅩⅢ型各占0.92%,12株结核分枝杆菌为单一的基因型。不同地区之间,以Ⅺ型为主要基因型,分别占各地区的86.8%、91.3%、78.95%、88.2%、95.05、89.3%。结论西藏地区的结核分枝杆菌存在明显的基因多态性,主要流行型为VNTRⅪ型(即北京家族基因型),初步研究结果显示北京家族基因型与卡介苗接种和耐药性无相关性。MLVA分型方法简单、快速,可以有效地用于结核分枝杆菌的基因分型和病原监测。  相似文献   

10.
目的 评价结核分枝杆菌基因组中串联重复序列(VNTR)位点在中国结核分枝杆菌临床分离株的分型鉴定的分辨力.方法 参考http://minisatellites.u_psud.fr/网站记载的位点选取其中VNTR位点,参照H37Rv结核分枝杆菌标准株全基因序列,利用DNAStar软件设计引物,采用PCR分别对中国结核分枝杆菌临床分离株和H37Rv标准株的VNTR位点进行检测,根据PCR凝胶电泳图片中各菌株相应位点扩增产物的大小,确定重复单元的重复次数.计算Hunter-Gaston指数来分析各位点的分辨能力,及各位点合并分辨力.结果 共检测135株中国结核分枝杆菌临床分离株和H37Rv标准株的45个VNTR位点.结果显示45个VNTR位点对136株菌的分辨力各不相同,Hunter-Gaston指数最大者为0.814(0.797~0.830),最小者为0.015(0.001~0.028),>0.5的有13个位点.位点的合并分辨力分析显示,随着位点数量增加,分辨力增强,如Qub11-b和Qub18两个位点合并分析,Hunter-Gaston指数为0.936,分组数为44组;Qub11-b、Qub18、Mtub21、Rv2372、MIRU26、Qub26、Qub4156c、Qub11-a和Qub15等9个位点合并分析,Hunter-Gaston指数已经达到1,组数为136组,表示已达到最大分辨力,即株水平分型.结论 不同VNTR位点具有不同的分辨力.其分型分辨力,多位点联合明显好于单位点.Qub11-b等9个位点的合并分型能力较好,这些位点有利于结核分枝杆菌的分型研究.  相似文献   

11.
China’s tuberculosis (TB) burden is second only to that of India worldwide. In Chongqing, the largest municipality in southwestern China, although the prevalence of both TB and drug-resistant TB is higher than in other municipalities, the molecular characteristics and drug susceptibility phenotypes are poorly known. In this study, 297 Mycobacterium tuberculosis isolates from Chongqing were genotyped with spacer oligonucleotide typing (spoligotyping) and 28-locus MIRU-VNTR (24-locus MIRU-VNTR scheme and 4 other loci). Spoligotyping results were compared with drug-resistant profiles. Patients who showed clustering by both spoligotyping and 28-locus MIRU-VNTR were interviewed to investigate their detailed contact history. Our data demonstrated that the Beijing genotype was the most prevalent genotype, and ST1 was the most predominant lineage in Chongqing. The Beijing genotype was significantly associated with ethambutol resistance and multidrug-resistant phenotypes. A combination of the 10 most polymorphic loci permitted to achieve higher discriminatory power than 24-VNTR. In addition, a presumed transmission pathway was observed in a cluster of patients with the same MIRU-VNTR profile. The 10-VNTR locus set is suitable for genotyping of Mycobacterium tuberculosis in Chongqing.  相似文献   

12.
Tuberculosis, caused by Mycobacterium tuberculosis (MTB) infection, remains a global health problem with increased concerns due to drug-resistant tuberculosis. However, molecular genotyping profiles may give insight of the transmission of TB in a particular region. The present study aimed to characterize the genetic diversity of drug-resistant MTB and evaluate primer sets applied for the epidemiological study of circulating MTB in Northeastern Thailand. A total of 92 MTB isolates, resistant to rifampicin and/or isoniazid, were collected from the Office of Disease Prevention and Control between 2013 and 2016. All isolates were genotyped by 24-locus MIRU-VNTR typing combined with spoligotyping. We also analyzed the distributions of drug susceptibility pattern and demographic data among different genotypes. In comparison with different loci sets, discriminatory power based on 12, 15, 24 standard primers were investigated. Eighty-six particular profiles were found; among the patterns, two clusters were produced in 8 strains. East African Indians (EAI) were the most prevalent strains (33 isolates, 35.87%) followed by Beijing (30 isolates, 32.61%), with 23 unknown isolates strains also found. The HGDI based on combination of 24 loci analysis and spoligotyping was 0.9962. The number of tandem repeat generated was highly discriminant (HGDI>0.6) at locus 580 (0.66), 960 (0.67), 2163b (0.73), 2165 (0.62), 2461 (0.68) 3690 (0.73) and 4052 (0.79), respectively. In contrast, the diversity at locus 154 and 2059 was not revealed. The results emphasized that 24-locus MIRU-VNTR and spoligotyping could be useful for epidemiological surveillance of drug-resistant MTB in this region. At a given allelic diversity, 7 primer sets containing MIRU04, MIRU10, QUB2163b, ETRA, ETRB, Mtub39 and QUB26 may be considered for screening the VNTR patterns. In addition, this study gathered both demographics and genotypic data within the same investigation for further tuberculosis prevention and control.  相似文献   

13.
China ranks second next to India among 22 high-burden countries despite decades' effort on tuberculosis (TB) control. The Sichuan province today contains the second-largest number of TB cases among Chinese provinces, where the prevalence of drug-resistant TB, especially MDR-TB, is much higher than the average level in eastern China. In this study, the population structure and the transmission characteristics of drug-resistant TB in Sichuan province were studied by spoligotyping and 24-locus Mycobacterial interspersed repetitive units-variable number tandem DNA repeats (MIRU-VNTR), applied to a total of 306 clinical isolates. Spoligotyping-based analysis showed that Beijing family represented 69.28% of all isolates and constituted the largest group (66.24%) of MDR-TB in Sichuan. The remaining isolates, accounting for 33.76% of MDR isolates, belonged to the ill-defined T family, Manu2, H3, LAM9, and other minor unassigned clades. The discriminatory power evaluated for spoligotyping was poor (HGI=0.595), but high for 24-locus MIRU-VNTRs (HGI=0.999). The number of the most discriminatory loci (h>0.6) was 12, including locus 424, 802, 960, 1644, 1955, 2163b, 2996, 3007, 3192, 3690, 4348 and 4052. It was concluded that 24-locus MIRU-VNTRs could be a more discriminatory tool for differentiating clinical isolates from Sichuan region. The small clustering size obtained from the current population structure analysis suggested that the high prevalence of drug-resistant TB in this region might be attributed partially to the acquired resistance due to inappropriate drug use rather than active transmission of drug-resistant TB (primary resistance).  相似文献   

14.
目的 评价间隔区寡核苷酸分型(Spoligotyping)和基于结核分枝杆菌散在分布数目可变串联重复序列分析(MIRU-VNTR)方法在重庆地区儿童结核病分子流行病学中的应用.方法 收集重庆地区210株儿童结核分枝杆菌(MTB)临床分离株,应用上述两种分型方法进行比较分析.结果 采用Spoligotyping分型方法,210株菌可分为2个基因群44种基因型,其中最大的1个基因群即北京家族(北京基因型)含有130株菌(61.90%).采用MIRU-VNTR分析发现24个位点的多态性差异较大,不同MIRU位点组合(12、15和24位点)的分辨率指数依次升高,后两个组合的差异是由位点ETR-B引起.各位点和各位点组合在北京家族菌株中的分辨率指数均高于非北京家族菌株.结论 重庆地区儿童MTB具有明显的基因多态性,其主要流行型为北京家族.在结核病原学监测中,可先采用Spoligotyping,再对成簇菌株进行15位点与ETR-B组合二次分型的联合分型策略,可提高分子流行病学调查效果.
Abstract:
Objective To evaluate the application of spacer oligonucleotide typing (Spoligotyping) and mycobaeterial interspersed repetitive unit-variable-number tandem repeat (MIRU-VNTR) analysis in the molecular-epidemiological study of tuberculosis and to discuss the characteristics of pediatric Mycobacterium (M.) tuberculosis strains in Chongqing. Methods M. tuberculosis strains isolated and typed by Spoligotyping and MIRU-VNTR respectively, from the children patients in Chongqing and to compare the results from both methods, epidemiologically. Results By means of Spoligotyping, 210 clinical isolates were divided into 2 gene groups, displaying 44 genotypes. Among them, the biggest group was M. tuberculosis Beijing family, including 130 strains (61.90%) ,using the Spoligotyping. From the results of MIRU-VNTR, 24 loci showed different polymorphism and the HGI of different loci set (12 old loci, 15 basic loci and 24-loci set) increased accordingly. The subtle difference in HGI was originated from one locus ETR-B, which was included in the 24-locus system. The diversity of each loci and MIRU-VNTR set for non-Beijing genotype strains was higher than that of the Beijing genotype strains. Conclusion In this study, it was preliminarily confirmed the existence of high polymorphism of M. tuberculosis while the Beijing Family was the main genotype and main prevalent strain in children of Chongqing area. Spoligotyping prior to 15-locus with ETR-B combination seemed more suitable for the massive epidemiological investigation of pediatric tuberculosis patients.  相似文献   

15.
Knowledge on basic characteristics of Mycobacterium tuberculosis (MTB) is helpful to understand the disease epidemiology and support the prediction of clinical outcome of the disease. The aim of this study was to detect the genotypes and genotypic characters of clinical Mycobacterium tuberculosis (MTB) isolates from new and retreatment rifampicin-resistant patients using three different genotyping methods. Mycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) typing was used to determine the diversity of 222 clinical isolates. Spoligotyping and IS6110-restriction fragment length polymorphism (RFLP) typing were also used to investigate the genetic characters of 105 MTB strains. Among the 15 genotypes detected by MIRU-VNTR, Beijing strains were the most prevalent of all strains (54.8%); new cases (40.5%) and retreatment cases (69.4%), followed by EAI strain. Spoligotyping categorized the strains into 11 lineages and 13 orphans whereas 96 different IS6110 patterns were identified using RFLP method. The mode number of IS6110 was 18 and 20. Higher band numbers were found in Beijing genotype (p < 0.001). Clustering rates by spoligotyping, MIRU-VNTR and IS6110-RFLP typing were 0.714, 0.004 and 0.085, respectively. Discriminatory powers of spoligotyping, MIRU-VNTR typing and IS6110-RFLP typing were 0.637, 1.000 and 0.997, respectively. Dominant Beijing genotype in both new and retreatment cases denoting that prevailing tuberculosis in Myanmar changed from EAI to Beijing lineage.  相似文献   

16.
Genotypes of Mycobacterium tuberculosis (MTB) are related to the geographic origin of the patients and population migration. The relationship between genotypes of MTB and clinical presentations has mainly focused on transmission of multi-drug resistant MTB strain in population. This study aimed to investigate the molecular epidemiology and dynamic change of MTB genotypes in Taiwan, and their association with clinical presentation among patients with pulmonary tuberculosis. A multi-center, two-year study which enrolled 516 patients with 516 MTB isolates was conducted, including: (1) 254 isolates from northern Taiwan; (2) 38 isolates from mid-western Taiwan; (3) 211 isolates from southern Taiwan; and (4) 13 isolates from the east coast of Taiwan. The isolates were genotyped with spoligotyping and standardized 12-loci-MIRU-VNTR method. The results showed Beijing/Beijing-like family was the major genotype of MTB in the northern (58%), eastern (53%), and southern (33%) regions. The second most widely spread lineage were the EAI-Manila (20% in the west and south) and Haarlem family (13-27% in the south, west, and east). According to the cluster analysis of 12-MIRU-VNTR genotypes, there were differences in distribution of MTB genotype between the northern and southern regions, and a temporal relationship between isolation year and 12-MIRU-VNTR genotype especially in loci 26 and 39 might exist. Furthermore, some patients with cavity lesions on chest films were associated with a cluster of Beijing family MTB strains, which can be defined by cluster analysis of 12-MIRU-VNTR genotype. However, the results of 12-loci-MIRU-VNTR genotyping in a longitudinal study should be interpreted with caution due to its short term instability. Further investigations of different molecular methodologies are necessary.  相似文献   

17.
The recent introduction of molecular methods has gained increased acceptance as a powerful tool for epidemiology and phylogeny of tuberculosis (TB). In this investigation, the efficiency of molecular typing using mycobacterial interspersed repetitive units (MIRUs) was assessed on a set of 116 Mycobacterium tuberculosis complex clinical isolates from 11 different geographic origins. The results obtained were compared with spoligotyping and variable number of tandem DNA repeats (VNTRs) typing data. Eighty-nine different MIRU profiles were obtained on the sample studied. Spoligotyping- or VNTR-defined clusters were split into subclusters by MIRU typing. Conversely, almost all of the clinical isolates clustered by MIRUs were shown to belong to spoligotyping-based defined clusters. The calculation of the discriminative power by the Hunter-Gaston index (HGI) for VNTR, spoligotyping and MIRU typing gave the values of, respectively, 0.959, 0.965 and 0.988, showing the high discriminative power of the MIRUs. The allelic diversity of the sample was calculated for each of the MIRU-VNTR loci; five MIRU loci (MIRU nos. 10, 23, 26, 31 and 40) were "highly discriminant", four (MIRU nos. 4, 16, 24 and 39) were "moderately discriminant", and three (MIRU nos. 2, 20 and 27) were "poorly discriminant". Among the three complementary VNTRs (exact tandem repeats ETR-A, ETR-B and ETR-C), ETR-A was the most discriminant locus. A combined numerical analysis of spoligotyping, VNTR and MIRU typing results partly corroborated a recently hypothesized evolutionary scenario for the M. tuberculosis complex. M. canettii would be the first branch to have diverged from a common M. tuberculosis complex ancestor. The East-African Indian (EAI) clade could be the first family to have diverged thereafter. A third branching separated a M. africanum-M. bovis clade, followed by a node separating Beijing versus non-Beijing M. tuberculosis. The Beijing clade was distinct from the Central Asian 1 (CAS1) family. Among non-Beijing strains, branches such as the Latin-American and Mediterranean (LAM), X and Haarlem clades diverged later. In conclusion, the results obtained show the congruence between clades defined by spoligotyping, and MIRU-VNTR, and underline the potential of these methods for M. tuberculosis phylogeny reconstruction. We also conclude that MIRU typing is a very promising method that may be used in a "two PCR-based" genotyping strategy, in conjunction to conventional epidemiological investigations.  相似文献   

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