The exploratory development of the related genes with rifampin and isoniazid in Mycobacterium tuberculosis / 中华检验医学杂志

ABSTRACT

Objective To detect the related genes with rifampin and isoniazid in Mycobacterium tuberculosis in sputums using the DNA chip technique and evaluate the fensibility of the clinical application of the DNA chip technique.Methods 586 sputum smear specimen was detected using the L-J cultivation to determine their drug resistance.Simultaneously.DNA chip was employed to detect the mutation of the frequent mutable points rpoB,katG/inhA in mycobaeterium tuberculosis isolates.These two assays were compared and samples showing discrepancy were chosen for additional sequencing to evaluate the accuracy of the detection.Results(1)There were 584 culture positive sputum smear specimens including 3(+)163 specimens,2(+)204 specimens,and 1(+)217 specimens.The drug fast results displayed that 361 strains were sensitive to INH,223 strains tolerated INH in which 93 strains tolerated it in low concentration while sensitive to it in high concentration.and 130 strains tolerated it in both low and high concentration.While 327 strains were sensitive to RFP.247 strains tolerated RFP in which 59 strains tolemted it in low concentration while sensitive to it in high concentration,and 188 strains tolerated it in both low and high concentration.(2)There were 367 positive strains(62.8%)and 217 negative strains(37.2%)identified by PCR amplification of the specific resistance gene fragments.The detection rate of the katG/inhA was 28.4%,and the mutation sites were mainly focused on the katG315(89.8%).The detection rate of the rpoB was 55.9%(137/247),and the mutation sites were mainly focused on rpoB531(68.6%)and rpoB 526(16.1%).(3)The sequencing of sample,which showed discrepancy with L-J cultivation and the DNA chip confirm a certain omission ratio.Conclusions It is feasible to detect the related resistant genes in Mycobacterium tuberculosis isolates using the DNA chip technique.The key factor is to raise the efficiency of the DNA extraction,the effciency of the PCR and the quality control of the experiment to facilitate its clinical application.