Quick Detecting Mutation Site of 315 Codon in katG Gene of INH resistant MTB by Stem-ring Molecular Probe in Liquid / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To detect 315 codon of mutation site in katG of isoniazid(INH)-resistant Mycobacterium tyberculosis(MTB) by stem-ring molecular probe quickly and detect out the fluorescence sign of hybridization between amplified products of katG 315 codon and probe in liquid by fluorescence spectrophotometer.The results were confirmed by sequencing.METHODS The software,Beacon designer,was used to design the katG 315 codon stem-ring molecular probe and the amplification system,and the relationship between the way and sequencing of the amplification products were compared.RESULTS The difference between PCR products from standard strain and INH-resistant one was significant in detecting the fluorescent light by use of fluorescence spectrophotometer.We detected fluorescent light signal between the 16 INH resistant strains and 10 H37RV standard strains.The resistant rate to INH detected was about 44%,and the rate of coincidence was about 97.5%.CONCLUSIONS The stem-ring molecular probe technology show high sensitivety in detecting mutation site of nucleic acid.The rate of coincidence is good between fluorescence spectrophotometer way and sequencing.