Abstract: Objective To develop a gene chip for the detection of pathogens causing genital ulcer diseases (GUDs). Methods Specific probes of 4 different pathogens were designed and synthesized. Gene chip was prepared by blotting the probes onto specially treated glass slides with the use of a robotics. Target genes of standard strains for the 4 different pathogens and the clinical specimens were amplified by PCR with Cy5 fluorescence labeled primers. The labeled amplicons were hybridized with gene chips, and then scanned and analyzed using computer software. Results The fluorescence signal for specific pathogen could be found in the gene chip, illustrating that one specific fluorescence signal denoted a single pathogen, and the combination of different signals denoted the corresponding co-existence of pathogens. Examination of 40 clinical specimens obtained from 40 patients with genital ulcers with gene chip was in good concordance with dark-field microscopy plus PCR or HSV culture plus PCR, showing Kappa values of 0.882 and 0.947, respectively. In addition, mixed infections were detected in 2 specimens. Conclusion Gene chip is a sensitive method with a reliable result and it can detect multiple infections simultaneously.

Key words: Oligonucleotide array sequence analysis, Sexually transmitted diseases