Specific Diagnostic for Members of Genus Mycobacterium

描述（由申请人提供）：提出了一种基于微阵列的新型系统，用于诊断结核病和结核样呼吸道感染。该诊断系统提供了一种平行的方法，用于筛查临床样本中是否存在结核分枝杆菌（人类结核病的病原体）和密切相关的分枝杆菌物种的DNA序列，同时筛查亲缘关系较远的分枝杆菌和已知引起结核样症状的其他常见感染病原体。该系统选择性地扩增目标DNA序列，使用重复的引物定向延伸。与PCR不同的是，这种方法产生短的延伸产物，其长度受到限制，因为使用一种构建块的形式，当它被纳入时终止延伸反应。将延伸反应限制为产生短延伸产物，可以用单一反应筛选许多病原体。该技术具有很强的选择性，因为只有当延伸反应产物与固定在微阵列上的探针杂交时才会产生信号。这要求：1)引物与目标DNA上的互补序列结合，2)得到的短延伸序列与用于检测延伸产物的微阵列上的探针互补。这两个过程都是选择性很强的。

DESCRIPTION (provided by applicant): A novel microarray-based system is proposed for diagnosis of tuberculosis and tuberculosis-like respiratory infections. This diagnostic system offers a parallel method to screen clinical samples for the presence of DNA sequences from Mycobacterium tuberculosis, the causative agent of human tuberculosis, and closely related mycobacterial species, while simultaneously screening specimens for more distantly related mycobacteria and other common infectious agents known to cause tuberculosis-like symptoms. The system selectively amplifies targeted DNA sequences using repeated rounds of primer-directed extension. Unlike the PCR, this method generates short extension products whose lengths are limited by using one of the building blocks in a form that terminates the extension reaction when it is incorporated. Restricting the extension reaction to the production of short extension products allows screening for many pathogens with a single reaction. The technique is very selective because a signal is produced only when the extension reaction products hybridize to probes immobilized on the microarray. This requires that: 1), the primer binds with a complementary sequence on the targeted DNA, and 2) the resulting short extension sequence is complementary to the probe on the microarray used to detect the extension product. Both of these are very selective processes.