青海高原237株结核分枝杆菌大片段基因多态性研究

摘要:目的 通过对青海高原结核分枝杆菌基因组大片段的检测，研究不同RDs（Regions of Difference）的多态性及其分型。方法 收集青海地区分离的结核分枝杆菌临床株237株，采用PCR方法对结核分枝杆菌基因组大片段RD105、RD181、RD150、 RD142及RD239基因的缺失进行检测。结果 237株菌中，根据RD105基因缺失鉴定出“北京家族”菌株220株，占92.83%；非“北京家族”菌株17株，占7.17%。根据RD181基因缺失将“北京家族”菌株分为现代“北京家族”结核分枝杆菌198株，占90.00%；RD181未缺失的古老非典型“北京家族”菌株22株，占10.00%。 RD150、RD142进一步又将现代“北京家族”结核分枝杆菌分为RD150、 RD142单缺失型及RD150与RD142共缺失型。首次发现6株菌缺失RD239基因，为印度-大洋洲系菌株。结论 青海地区结核分枝杆菌RD基因型丰富，主要流行菌株以缺失RD105的“北京家族”菌株为主。

Study on large fragment polymorphism and genotypes of Mycobacterium tuberculosis strains isolated from Qinghai plateau

Abstract: Objective The aim of this article was to study large fragment polymorphism and genotypes of Mycobacterium tuberculosis strains isolated from Qinghai plateau.Methods A total of 237 clinical isolated M. tuberculosis strains in Qinghai province were collected and genotyped by PCR for detecting for the deletions of RD105, RD181, RD150, RD142 and RD239. Results Among 237 isolates of Mycobacterium tuberculosis isolates, 220 were identified as "Beijing family" and 17 were "non-Beijing family" by RD105 deletion, accounting for 92.83% and 7.17% respectively. The 220 "Beijing family" were further identified by RD181 deletion as the modern "Beijing family" (198 isolates, 90.00%) and atypical "Beijing family" (22 isolates, 10.00%). RD150 and RD142 further divided modern "Beijing family" into genotypes of single RD150 deletion, single RD142 deletion and concurrent RD150 and RD14 deletion. RD239 deletion was first found in six strains, which belonged to India-ocean lineage.Conclusion RD105 deleted "Beijing family" strains of Mycobacterium tuberculosis prevailed in Qinghai and displayed at least six RD genotypes.