Abstract: Objective To establish a multiplex PCR genotyping method for Chlamydia trachomatis isolates. Methods With the aid of the special gene software, the homogenicity of C.trachomatis D-K omp1 gene was analysed, and the primers for genotyping were designed accordingly. The differences of amplified products of each genotype were over 80 bp so that they could be distinguished on agarose gel electrophoresis. The multiplex PCR was applied to test the reference and wild strains and was compared with PCR-RFLP method. Results After repeated experiments, each reference strain was amplified to reveal a clear band by the multiplex PCR which could be differentiated with each other on agarose gel electrophoresis. All wild strains could be genotyped by the multiplex PCR while 94.44% of the strains could be genotyped by PCR-RFLP. Conclusion The multiplex PCR genotyping method for C.trachomatis is a sensitive, specific, convenient and practical tool for clinical application.

Key words: Polymerase chain reaction, Genotype, Chlamydia trachomatis