Abstract: Objective To develop a DNA chip combined with multiplex PCR for detecting 3 prevalent pathogens of urogenital infections and their drug-resistance. Methods The primers and probes targeting the conservative sequences of Neisseria gonorrhoeae, Chlamydia trachomatis and Ureaplasma urealyticum were designed for the detection of the pathogens. And the primers and probes targeting gyrA, parC, 16 srRNA and tetM sequences were designed for detecting fluoroquinolone, spectinomycin, tetracycline-resistant Neisseria gonorrhoeae and tetracycline-resistant Ureaplasma urealyticum. These probes were used for fabricating a DNA chip. The total DNA was isolated from 152 genital clinical isolates, and the target DNA was amplified by multiplex PCR, labeled with Cy5 fluorescence, and then hybridized with the DNA chip. The scanarray 4 000 system was used for scanning and analysing the results. Results The sensitivity of the DNA chip is 0.01 fg plasmid DNA. The results detected by the DNA chip were completely consistent with those of clinical routine tests (k>0.8). Conclusions This DNA chip combined with multiplex PCR is a rapid diagnostic assay with high specificity and sensitivity for the detection of Neisseria gonorrhoeae, Chlamydia trachomatis and Ureaplasma Urealyticum and their drug-resistance, and may be applied in the diagnosis of urogenital infections.

Key words: Neisseria gonorrhoeae, Chlamydia trachomatis, Ureaplasma urealyticum, Oligonucleotide array sequence analysis, Microbial sensitivity tests