Background: Chlamydia trachomatis is the leading cause of bacterial sexually transmitted diseases (STDs) world-wide. The aim of this study was to characterize the C. trachomatis genetic profiles of clinical isolates in the Korean population by sequence analysis of the ompA gene.
Methods: Endocervical specimens from patients who were confirmed as C. trachomatis infection by real-time PCR were used for ompA sequencing. The individual sequences (about 890 nucleotides) were determined by comparison with those from known C. trachomatis strains using the BLAST search tool. Sequence variations were analyzed by comparing them with sequences from prototype strains.
Results: Sequence analysis using BLAST similarity search of the ompA gene from the 106 clinical isolates revealed that the most prevalent genotype corresponded to E (n = 28, 26.2%), followed by F (n = 20, 18.9%), D (n = 16, 15.1%), J (n = 16, 15.1%), G (n = 9, 8.5%), H (n = 8, 7.5%), K (n = 5, 4.7%), B (n = 2, 1.9%), and I (n = 2, 1.9%). Detailed sequence analysis based on comparison with each prototype revealed that there are sequence differences in 44 specimens (41.5%).
Conclusions: This study is the update on the distribution of C. trachomatis ompA genotypes in Korea in more than a decade. The genotypes have become more diversified, with genotypes K, B, and I being newly detected. C. trachomatis genotyping is crucial for regional and global epidemiological studies, as well as for vaccine development.