间隔区寡核苷酸分型和多位点可变数量串联重复序列分析在结核分枝杆菌基因分型中的应用

目的评价间隔区寡核苷酸分型(Spoligotyping)及多位点可变数量串联重复序列分析(MLVA)方法在结核分枝杆菌基因分型研究中的应用。方法收集224株结核分枝杆菌临床分离株,分别采用Spoligotyping及MLVA方法进行基因分型,比较两种方法的分型效果,评价两种方法在结核分枝杆菌基因分型中的应用。结果使用Spoligotyping方法,224株结核分枝杆菌呈现出55种基因型,39株具有独特的基因型,其余185株菌呈现出16种基因型;使用MLVA方法时,224株结核分枝杆菌呈现出160种基因型,132株具有独特的基因型,余下的92株菌呈现出28种基因型;当两种方法联合使用时,224株结核分枝杆菌呈现出179种基因型,159株结核分枝杆菌具有独特的基因型,余下的65株菌表现为20种基因型。湖南省和安徽省的菌株中北京家族菌株所占的比例差异有统计学意义(P<0.001),安徽省北京家族菌株所占的比例明显高于湖南省。结论MLVA在结核分枝杆菌株水平的鉴定方面,其分辨能力高于Spoligotyping,但是Spoligotyping在鉴定北京家族菌株和M.bovis方面有一定的优势。将Spoligotyping方法作为一线分型技术,MLVA作为二线分型技术联合应用时,将提高结核病的流行病学调查和病原学监测效果。不同地区的菌株有不同的特点。     

河南省结核分枝杆菌间隔区寡核苷酸分型技术的应用研究

目的研究间隔区寡核苷酸序列(Spoligotyping)基因分型技术在河南省结核病分枝杆菌基因分型中的应用,了解河南省基因型种类和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年在河南省结核病防治机构实验室分离培养的310株结核分枝杆菌,设计引物,应用PCR和间隔区寡核苷酸分型(Spoligotyping)技术对结核分枝杆菌进行分型检测分析,基因分型分析经http://www.miru-vntrplus.org/MIRU/index.faces网站分析,统计学数据经卡方检验。结果对310株结核分枝杆菌临床分离株的Spoligotyping结果显示分为4个基因群(Beijing和Beijing近似群、T群、Manu群、S群),24个基因型,有267株为北京家族基因型,占86.1%,且北京家族基因型与MDR耐药有相关性;河南省较年轻人群(<60岁)感染的结核分枝杆菌中,北京家族基因型所占比例高于年老组(即>60岁组),北京家族基因型与年轻组的联系强于年老组;北京家族基因型的分布在不同的地区间有差异。结论河南省结核分枝杆菌以北京家族基因型为主要流行型,且与耐药及年龄、地域有相关性,重点监测北京家族基因型。     

结核分枝杆菌传播的分子流行病学特征

目的探讨结核分枝杆菌传播的基因型特征及其对于耐药结核菌近期传播的影响。方法选取13个社区作为监测点,应用分枝杆菌散在重复单位(MIRU)技术分析结核分枝杆菌DNA多态性。结果 558株结核分枝杆菌的12个MIRU位点检测产生143个基因型,其中成簇基因型66个,成簇率86.2%;74.6%的菌株属于北京家族,177个菌株(31.7%)属于山东基因型;耐多药菌株的近期感染估计值(46.7%)明显低于全敏感菌株(72.7%)。结论山东基因型菌株具有较强的在人群中传播的能力、较高的耐药性以及对抗督导化疗的能力;利用基因分型技术开展结核病监测可以有效促进结核病控制工作。     

上海市2000-2002年91株结核分枝杆菌分子流行病学分析

目的探讨上海地区结核病分子流行病学特点。方法对从上海市疾病预防控制中心菌株库中随机抽取的2000—2002年各50株耐药和敏感菌株进行间隔区寡核苷酸分型（Spoligotyping）和分枝杆菌散在分布重复单位（MIRU）基因型分型，并结合流行病学资料进行分析。结果抽样菌株中，具有特异Spoligotyping指纹图谱的北京基因型菌株在上海地区分布达89％（81／91）。未接种过卡介苗（BCG）的患者中北京基因型菌株占88．5％（54／61），接种过BCG的患者中北京基因型菌株占90％（27／30），差异无统计学意义。北京基因型菌株耐药率为45．7％（37181），低于非北京基因型菌株的耐药率60．0％（6／10），差异无统计学意义。MIRU成簇菌株占所有菌株的62．6％（57／91）。结论北京基因型菌株在上海地区有广泛分布，北京基因型菌株与BCG接种和耐药无关，结核病患者中有部分是由于近期传播而引起的。     

344株结核分枝杆菌的基因分型研究

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。     

中国部分地区结核分枝杆菌北京基因型菌株分布初步分析

目的初步了解结核分枝杆菌北京基因型菌株在中国不同地区的分布情况。方法采用间隔区寡核苷酸分型(spacer oligonucleotide typing,Spoligotyping)方法对1 603株分离自7个省、市、自治区的结核分枝杆菌进行分型分析,确定北京基因型菌株在不同地区所占的比例。结果根据Spoligotyping分型结果及北京基因型菌株的定义,1 603株结核分枝杆菌中1 158株为北京基因型菌株,占72.24%。北京地区北京基因型菌株所占的比例最高为92.59%,其后依次为西藏(90.38%),吉林(89.88%),陕西(80.00%),新疆(65.36%),广西(55.29%),福建(54.50%)。结论北京基因型菌株为主要的流行菌株,但是不同地区北京基因型菌株所占的比例并不相同,北方地区北京基因型菌株的比例高于南方地区。     

山东地区结核分枝杆菌临床菌株基因型特征研究

目的 探讨山东地区结核分枝杆菌临床分离菌株的基因型特征,评估不同基因型分布对于耐药结核菌近期传播的影响.方法 在山东地区选取13个结核病防治机构作为监测哨点收集临床分离菌株和相关信息,应用分枝杆菌散在重复单位(MIRU)技术分析结核分枝杆菌DNA多态性.结果 1年的研究期内共获得558株结核分枝杆菌,对12个MIRU位点进行检测共产生143个基因型,其中成簇基因型66个,成簇率86.2%.74.6%的菌株属于北京家族,177个(31.7%)菌株属于山东基因型.耐多药菌株的近期感染估计值明显低于敏感菌株.结论 山东地区结核分枝杆菌具有明显的基因多态性,山东基因型菌株在人群中具有较强的传播能力.     

MIRU技术在结核杆菌基因分型中的应用

目的建立结核分枝杆菌散在分布重复单位(MIRU)基因分型法,应用于突发疫情结核病原的分型检测。方法采用简单数字表法随机抽取宁波市江北区2009-2011年保存的结核菌株,对其进行MIRU分型,同时对2011年一起学校结核突发疫情的病原进行分型检测,比较成簇性,分析传播的危险性。结果 29株江北区2009-2011年菌株MIRU分型结果分为22种不同的MIRU基因型,成簇性低;而一起学校结核突发疫情6份样本MIRU基因型分型结果为同一种MIRU基因型,成簇性高,传播危险性大。12个MIRU位点的多态性分析表明各位点有较大区别(h值为0.67～0.87之间)。结论 MIRU分型方法简单快速,其数字化结果清晰可靠,是一种有效的结核分枝杆菌基因型分型方法。应用于突发疫情病原分析,能有效控制疫情蔓延。     

分枝杆菌分子分型方法的选择及应用进展

分子分型是结核病（TB）研究中相对新的领域。但已成为TB研究的重要方法。目前公认的方法是插入序列IS6110 RFLP。其它如间隔寡核苷酸分型（Spoligotyping）和分枝杆菌散布重复单元（MIRU）等也有了越来越多的应用。对于研究TB传播动力学；证实可疑暴发；区分新感染、再感染和复燃等。基因分型提供了许多重要的新结论。分子技术的出现也为进一步研究M．TB的传播和种系发生特征提供了新的途径。本文综述近年来分子分型技术在TB流行病学中的新应用以及如何使用分子技术探讨特定问题。     

甘肃省228株结核分枝杆菌临床分离株Spoligotyping分型研究

目的利用间隔区寡核苷酸分型(Spoligotyping)方法对甘肃省结核分枝杆菌流行株进行分型研究,了解目前甘肃省结核分枝杆菌流行株基因型的基本情况,为甘肃省结核病防控提供分子流行病学依据。方法采用Spoligo-typing对甘肃省228株临床分离结核分枝杆菌进行基因分型,结果使用Bionumerics-5.01软件统计、分析,并与SpolDB4数据库进行比对,得出菌株分型结果。结果228株结核分枝杆菌被分为北京家族(Beijingfamily)和非北京家族(Non-Beijingfamily)2大基因群,其中北京家族基因群占88.6%(202/228)。非北京家族基因群为11.4%(26/228),228株结核分枝杆菌构成23个基因簇,其中独立基因型12个。结论北京家族基因群菌株在甘肃省结核分枝杆菌流行株中占据绝对优势地位,对该基因群菌株引发的结核病应给予密切关注并应加强对北京家族基因型菌株生物学特性研究。     

Differentiation of tuberculosis strains in a population with mainly Beijing-family strains

A high prevalence of tuberculosis (TB) isolates that are genetically homogenous and from the Beijing family has been reported in Russia. To map TB transmission caused by these strains, new genotyping systems are needed. Mycobacterial interspersed repetitive units (MIRUs) offer the possibility of rapid PCR-based typing with comparable discrimination to IS6110 restriction fragment length polymorphism techniques. Spoligotyping and detection of IS6110 insertion in the dnaA-dnaN region were used to identify Beijing strains in 187 Mycobacterium tuberculosis isolates from Samara, Russia. The Beijing isolates were analyzed by using 12-MIRU and 3-exact tandem repeats (ETR) loci and by an expanded set of 10 additional variable number tandem repeats loci. The expanded set of 25 MIRUs provided better discrimination than the original set of 15 (Hunter-Gaston diversity index 0.870 vs. 0.625). Loci MIRU 26, 1982, and 3232 were the most polymorphic in Beijing isolates.     

不同串联重复序列位点组合用于中国结核分枝杆菌基因分型的能力比较分析

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.     

Role of spoligotyping and IS6110-RFLP in assessing genetic diversity of Mycobacterium tuberculosis in India

In the present study, genetic diversity analysis of Mycobacterium tuberculosis isolated from patients attending a tertiary care hospital, North India, has been attempted. Eighty three isolates of M. tuberculosis were subjected to DNA fingerprinting using spoligotyping and IS6110-RFLP techniques. Spoligotype patterns showed that central Asian (32.5%), ill defined T (13.2%) and Beijing (10.8%) families were predominant in ongoing transmission of the bacterium. Two STs; ST26 (CAS_Delhi) and ST1 (Beijing) represented 36.1% of the total M. tuberculosis population in eastern Uttar Pradesh, North India. IS6110 RFLP analysis showed that isolates having low and zero copy number of the IS element were 15.6% and 19.2%, respectively. Out of the 47 isolates clustered by spoligotyping, 40 could be further differentiated as unique strains by IS6110-RFLP. Therefore, this study recommends that both the techniques be used simultaneously for DNA fingerprinting of M. tuberculosis in India.     

四川省结核分枝杆菌VNTR分型研究

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。     

北京、广东、宁夏三地结核分支杆菌DNA指纹的应用研究

目的 分析“北京家族”结核分支杆菌,从分子流行病学角度探讨北京、广东及宁夏三地结核分支杆菌的分布特征。方法 采用Gel compare4．1软件对来自三地的206株结核分支杆菌的插入序列IS6110 DNA指纹图谱进行数字化,经互联网与世界结核分支杆菌DNA指纹库进行相似性比较;同时应用该软件对上述菌株行聚类分析;构建标准的结核分支杆菌Spoligotyping(间隔区寡核苷酸分型法)DNA指纹方法;用χ^2检验比较不同组别肺结核病人临床分离菌株成簇率的差别,同时计算相对危险度(OR)。结果 206株结核分支杆菌的IS6110 DNA指纹图谱与DNA指纹图谱库相比较,未发现相同者。56．8％(117／206)的结核分支杆菌IS6110 DNA指纹相似值在1．00—0．65之间,且它们的Spo1igotyping指纹图谱均与“北京家族”结核分支杆菌相一致;分组统计显示：男性组与女性组、年龄≥42岁组与＜42岁组成簇率之间差异有显著性(P＜0．05),OR值为男性4．43,95％CI：0．94—28．76;＜42岁为5．06,95％CI：1．00—34．34。其他各组之间差异无显著统计学意义(P＞0．05)。结论 “北京家族”结核分支杆菌在三地呈较高水平的流行;结核分支杆菌在男性和＜42岁人群中的传播频率较女性和≥42岁人群为高,且男性和＜42岁可能是三地结核病近期传播的危险因素。利用结核分支杆菌的DNA指纹图谱和互联网技术,可以实现结核分支杆菌传染源全球范围的追踪。     

Efficient Differentiation of <Emphasis Type="Italic">Mycobacterium tuberculosis</Emphasis> Strains of the W-Beijing Family from Russia using Highly Polymorphic VNTR Loci

The W-Beijing family is a widespread Mycobacterium tuberculosis clonal lineage that frequently causes epidemic outbreaks. This family is genetically homogeneous and conserved, so ETR-VNTR (exact tandem repeat-variable number of tandem repeats) typing is insufficient for strain differentiation, due to a common ETR-A to E profile (42435). This leads to the false clustering in molecular epidemiological studies, especially in the regions of predominance of the W-Beijing family. In this study, we searched for VNTR loci with a high evolutionary rate of polymorphism in the W-Beijing genome. Here we further evaluated VNTR typing on a set of 99 Mycobacterium tuberculosis clinical isolates and reference strains. These isolates were characterized and classified into several genotype families based on three ETR loci (A, C, E) and eight additional loci [previously described as QUB (Queen’s University Belfast) or MIRU (Mycobacterial Interspersed Repetitive Units) or Mtubs]. Ninety-nine strains were divided into 74 VNTR-types, 51 isolates of the W-Beijing family identified by IS6110 RFLP-typing (the restriction fragment length polymorphism-typing) and/or spoligotyping were subdivided into 30 VNTR-types. HGDI (the Hunter–Gaston discriminatory index) for all studied loci was close to that of IS6110 RFLP typing, a “gold standard” method for subtyping M. tuberculosis complex strains. The QUB 26 and QUB 18 loci located in the PPE genes were highly polymorphic and more discriminative than other loci (HGDI is 0.8). Statistically significant increase of tandem repeats number in loci ETR-A, -E, QUB 26, QUB 18, QUB 11B, Mtub21 was revealed in the W-Beijing group compared to genetically divergent non-W-Beijing strains. Thirty-six isolates were subjected to IS6110 RFLP typing. The congruence between results of the IS6110 RFLP typing and 11-loci VNTR typing was estimated on 23 isolates of the W-Beijing family. These isolates were subdivided into 9 IS6110-RFLP types and 13 VNTR types. The poor profiles correlation (0.767) reflects the differences in the rate and type of evolution between genome regions targeted by IS6110-RFLP and VNTR typing. VNTR typing in proposed format is powerful tool for discrimination of M. tuberculosis strains with different level of genetic relationship.     

杭州地区结核分枝杆菌氧氟沙星耐药株的MIRU-VNTR基因分型研究

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。     

First case of multidrug-resistant tuberculosis caused by a rare “Beijing-like” genotype of Mycobacterium tuberculosis in Bogotá, Colombia

This report describes a first case due to a genetically distinct and relatively rare “Beijing-like” strain of Mycobacterium tuberculosis isolated from a 15 years old female patient who died shortly after the initiation of antituberculous therapy with second-line drugs. Positive cultures obtained from lung, kidney and adrenal glands upon autopsy were identified as Mycobacterium tuberculosis complex characterized by an identical 15-banded IS6110-RFLP pattern, and were found to be resistant to all the 4 first-line antituberculous drugs tested (rifampin, isoniazid, ethambutol and streptomycin). Spoligotyping followed by comparison with the SITVIT2 database revealed that the isolate belonged to a rare pattern identified as Spoligotype International Type SIT190, which represents only 1.7% of all the Beijing strains worldwide. We present data on its worldwide distribution and present an evolutionary scenario based on available MIRU typing data.     

Differentiation of highly prevalent IS6110 single-copy strains of Mycobacterium tuberculosis from a rural community in South India with an ongoing DOTS programme.

We have prospectively analysed the DNA fingerprinting of Mycobacterium tuberculosis strains in a rural community from high prevalence area in South India with an ongoing DOTS programme. Strains from 451 culture-positive cases, diagnosed during July 1999-December 2000, were fingerprinted initially by both IS6110 and DR probes followed by polymorphic GC-rich repeat sequences (PGRS) typing only on low-copy strains. The results were correlated with selected epidemiological and clinical data. Forty one percent of strains showed single copy of IS6110, which further got differentiated into 62 DR and 27 PGRS patterns. One predominant DR pattern (5B/2) was found in 20% of the low-copy strains and was also involved in clusters. In all, 183 patients out of 451 (40%) were clustered in total 44 clusters when analysed by IS6110 and DR probes. With additional PGRS typing, the number of patients clustered was further reduced to 106 (23%). More number of patients (131) were clustered in IS6110 single-copy group. The maximum number of clusters was found with two or three patients. Only a small percentage (16%) of the patients reported direct epidemiological links while remaining patients might have had indirect links or casual contacts. Thus, a combination of two to three genetic markers is able to differentiate the most endemic strains of M. tuberculosis in areas with a high incidence of tuberculosis. The epidemiological data do not suggest any major outbreaks or a hot-spot hypothesis of transmission in this region. Phylogenetic analysis using IS6110, DR and PGRS RFLP (restriction fragment length polymorphism, RFLP) fingerprints showed that isolates exhibited clonal evolutionary pattern. The predominance of certain genotypes and agreement between the phylogenetic trees indicated that these strains were closely related and might have evolved or propagated from the common ancestor.     

Genotypes and genetic characters of Mycobacterium tuberculosis from Myanmar using three typing methods

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.