论文部分内容阅读
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)两种分型方法在西藏地区结核病分子流行病学中的应用。方法收集西藏地区结核分枝杆菌(Mycobacterium tuberculosis)临床分离株,应用Spoligotyping及MLVA两种分型方法进行比较分析。结果共在西藏地区收集到216株结核分枝杆菌临床分离株,采用Spoligotyping分型方法,216株菌可分为3个基因群13种基因型,其中最大的1个基因群即北京家族(Beijing family)含有195株菌,占90.28%。北京家族菌株中,有BCG接种史者占45.64%(89/195),无BCG接种史者占54.36%(106/ 1195),两者间的差异无统计学意义(x~2=0.059,P>0.05)。采用MLVA分型方法,216株菌可分成19个基因群108种基因型,其中80种基因型只有1株菌,占37.03%(80/216),另有136株菌表现出28种基因型,成簇数为28,占62.96%(136/216)。在20个VNTR位点的等位基因多态性发现Miru31位点的多态性最高,多态性指数(h)达到0.77,而Mtub29、Mtub12位点的多态性较差,都低于0.05。其中Mtub02位点可鉴别北京家族和非北京家族,它鉴别的北京家族与Spoligotyping鉴别的北京家族符合率达到100%。结论西藏地区结核分枝杆菌具有明显的接引多态性,其主要流行型为北京家族。北京家族菌株与BCG接种无相关性。应用Spoligotyping和MLVA两种分型方法进行结核病流行病学研究,将提高结核病的流行病学调查和病原学监测效果。
Objective To evaluate the application of two genotyping methods, Spoligotyping and MLVA, in molecular epidemiology of tuberculosis in Tibet. Methods The clinical isolates of Mycobacterium tuberculosis in Tibet were collected and compared by Spoligotyping and MLVA. Results A total of 216 clinical isolates of Mycobacterium tuberculosis were collected in Tibet. Spoligotyping method was used to classify 216 strains of bacteria, which could be divided into 13 genotypes of 3 gene groups. The largest one was Beijing family Family contains 195 strains, accounting for 90.28%. Among Beijing family strains, there were 45.64% (89/195) of BCG inoculation history and 54.36% (106/1195) without BCG inoculation history, the difference was not statistically significant (x ~ 2 = 0.059, P > 0.05). Using MLVA typing method, 216 strains were divided into 19 genotypes and 108 genotypes, of which 80 genotypes had only one strain, accounting for 37.03% (80/216), and another 136 strains showed 28 genotypes , The number of clusters is 28, accounting for 62.96% (136/216). Polymorphisms of Miru31 locus at the 20 VNTR loci were found to be the highest, with a polymorphism index (h) of 0.77 and a poorer polymorphism of Mtub29 and Mtub12 loci below 0.05 . Among them, the Mtub02 locus can identify Beijing families and non-Beijing families, and its identification of Beijing family and Spoligotyping identified Beijing family in line with the rate of 100%. Conclusion Mycobacterium tuberculosis in Tibet has obvious polymorphism, and its main epidemic type is Beijing family. There was no correlation between Beijing family strains and BCG inoculation. The application of Spoligotyping and MLVA genotyping methods for tuberculosis epidemiology will improve the epidemiological investigation and the etiological monitoring effect of tuberculosis.