Abstract: Objective To utilize the high-scale and high efficiency of DNA chip to develop a rapid,simple , and specific method for identification of Mycobacterium species, to provide a basis for the correct diagnosis of mycobacterium diseases. Methods DNA sequencing was used as the control, the target DNA fragments of 28 Mycobacterium reference strains,9 non-Mycobacterium strains and 465 Mycobacterium isolates were analyzed by PCR-SSCP and DNA chip. Results The reference strains of 28 Mycobacteria and 9 non-Mycobacteria were analyzed by DNA chips, the Results showed that the DNA chip was specific. Of 465 mycobacterium Clinical isolates, 256 strains were identified as Mycobacterium tuberculosis complex(MTBC)with PCR-SSCP,and were positive hybridization with Mycobacterium genus probe M and MTBC-specific probe a on DNA chip.209 strains were identified as non-tuberculosis mycobacteria with PCR-SSCP,and their species were identified by DNA chips as follows: 68 were M. chelonae, 46 were M. intracellulare, 34 were M. kansasii, M. gastri, M. scrofulaceum , M. simiae complex,31 were M. fortuitum, 16 were M. gordonae,3 were M. avium,2 were M. marinum and M. abscess complex, 1 was M. terrae, 1 was M. diernhoferi, and 1 was M. phlei. 6 strains that were only positive hybridization with probe M were sequenced and showed that 5 were M. intracellulare, which had different DNA sequences with the reference strain, and 1 was M. neoaurum. There is not specific probe for M. neoaurum on DNA chip. Conclusion It might be a simple, rapid, sensitive and specific method for identification of most Mycobacterium species byDNA chip, and it could raise correct diagnosis rate of Mycobacterium diseases, and direct the physicians toperform rational chemotherapy.

Key words: Mycobacterium, Polymerase chain reaction, Single-stranded conformation polymorphism, Species identification, DNA chip