Fingerprinting by random amplified polymorphic DNA of M tuberculosis and its application

Objective Epidemiological studies on Mycobacterium tuberculosis in Chongqing. Methods To establish a fingerprinting method by random amplified polymorphic DNA and polyacrylamide gel electrophoresis (RAPD PAGE). The fingerprints of genomic DNA of M tuberculosis strains, which were isolated from 416 sputum specimens among the 287 lung tuberculosis patients, were detected by RAPD PAGE fingerprinting with primer 1 (5′ CCGGGGCGGTTC) and primer 2 (5′ CCGCCGACCGAC). Results Seven types of DNA fingerprints were found and the main types were type Ⅰ (35.5%), type Ⅱ (29.3%) and type Ⅲ (22.6 %). In those main type groups, the first treated patients aged from 20 to 39 and from 40 to 49 were 58.0% and 46.2% respectively. For type Ⅰ, type Ⅱ and type Ⅲ, the first treated patients were 52.0%, 46.4% and 58.5%, the first treated with the anti tuberculosis chemicals, the multi drug resistant (MDR) strains were 11.3%, 35.9% and 24.3%. Conclusions The RAPD PAGE fingerprinting is an useful method to type M tuberculosis strains. The prevalence of tuberculosis resisting to rifampin in Chongqing city is primarily due to the transmission of type Ⅰ, Ⅱ and Ⅲ strains.