CAJ | 학술논문

目的应用分子遗传学方法探讨234株北京谱系结核分枝杆菌的起源进化及群体间基因流动特征.方法对来源于中国北方五省区(黑龙汀、吉林、辽宁、内蒙古和宁夏)234株北京谱系结核分枝杆菌进行24位点可变数目串联重复序列(VNTR)基因分型,计算各VNTR位点的等位基因多态性(h)；从个体水平分析其系统发育,即构建NJ树和最小生成树；构建群体水平系统发育树,并在此基础上通过贝叶斯模型计算最近共祖年代；通过分子方差分析了解五省区菌株间的基因流动情况.结果 24个VNTR位点的等位基因多态性较低(h值:0.000 ～ 0.744).234株北京谱系结核分枝杆菌分散存在NJ树各个进化分支,最小生成树中约62.0％(145/234)的菌株被划分到同一“克隆复合群”.群体水平系统发育树显示234株菌与MIRU-VNTRplus数据库(http://www.miru-vntrplus.org)中的北京谱系结核分枝杆菌的遗传关系最近(Bootstrap值为100)；最近共祖年代为5308年(95％CI:4263 ～ 6470年).通过分子方差分析发现吉林与黑龙江、辽宁菌株之间,内蒙古与宁夏菌株之间遗传分化系数的差异无统计学意义(P＞0.05).结论中国北方五省区北京谱系结核分枝杆菌的遗传相似性较高,菌株间种系发生关系不明显.推测这些菌株由近期(约5000年前)结核分枝杆菌北京谱系的某一“克隆”进化而来.地理位置接近的区域,菌株间存在基因流动现象.
목적 응용분자유전학방법탐토234주북경보계결핵분지간균적기원진화급군체간기인류동특정.방법 대래원우중국북방오성구(흑룡정、길림、료녕、내몽고화저하)234주북경보계결핵분지간균진행24위점가변수목천련중복서렬(VNTR)기인분형,계산각VNTR위점적등위기인다태성(h)；종개체수평분석기계통발육,즉구건NJ수화최소생성수；구건군체수평계통발육수,병재차기출상통과패협사모형계산최근공조년대；통과분자방차분석료해오성구균주간적기인류동정황.결과 24개VNTR위점적등위기인다태성교저(h치:0.000 ～ 0.744).234주북경보계결핵분지간균분산존재NJ수각개진화분지,최소생성수중약62.0％(145/234)적균주피화분도동일“극륭복합군”.군체수평계통발육수현시234주균여MIRU-VNTRplus수거고(http://www.miru-vntrplus.org)중적북경보계결핵분지간균적유전관계최근(Bootstrap치위100)；최근공조년대위5308년(95％CI:4263 ～ 6470년).통과분자방차분석발현길림여흑룡강、료녕균주지간,내몽고여저하균주지간유전분화계수적차이무통계학의의(P＞0.05).결론 중국북방오성구북경보계결핵분지간균적유전상사성교고,균주간충계발생관계불명현.추측저사균주유근기(약5000년전)결핵분지간균북경보계적모일“극륭”진화이래.지리위치접근적구역,균주간존재기인류동현상.
Objective Using methodology of molecular genetics to explore the origin,phylogen,and gene flow of Mycobacterium tuberculosis (MTB) Beijing lineage in the five provinces from northern China,including Heilongjiang,Jilin,Liaoning,Neimenggu and Ningxia.Methods 234 MTB Beijing lineage strains were genotyped by 24 Variable Number Tandem Repeat (VNTR),and the h (the allelic diversity) value of each VNTR locus was calculated.On individual level of phylogeny,it was constructed Neighbor-Joining (N-J) tree and minimum spanning tree (MST).Phylogenetic tree was built at the population level,and the most recent common ancestor (TMRCA)was estimated through Bayesian model.Molecular variance (AMOVA) was used to understand the gene flow among strains discovered from the five provinces.Results Allelic diversities of the 24VNTR loci were low (h:0.000-0.744).234 strains of MTB Beijing lineage were dispersed in individual branch of the N-J tree,with 62.0％ (145) of them grouped to the same "colonial complexes" in MST.At the population level,the evolution relationship of 234 strains appeared the closest to Beijing lineage,which was from MIRU-VNTRplus database,and the bootstrap was 100.The TMRCA was 5308 (95％ CI:4263-6470) years.Differences of pairwise Fst values acquired by AMOVA between Jilin and Heilongjiang,Liaoning,Neimenggu and Ningxia,were not statistically significant (P＞0.05).Conclusion The genetic similarity of Beijing lineage MTB from the five provinces of northern China was high.The phylogeny branches had no characteristic dispersal in each province.It was speculated that these strains showed an evolution from a clone of MTB Beijing lineage (about 5000 years ago).The gene flow was taking place between neighboring zones.