Global Multilocus Sequence Type Analysis of Chlamydia trachomatis Strains from 16 Countries.

Area of Science:

• Microbiology
• Genetics
• Epidemiology

Background:

• The Uppsala University Chlamydia trachomatis multilocus sequence type (MLST) database compiles genetic information from various studies.
• The database utilizes five target regions (non-housekeeping genes) and the ompA gene for strain characterization.

Purpose of the Study:

• To analyze Chlamydia trachomatis MLST sequence types (STs) globally.
• To identify STs with significant geographical spread.
• To evaluate the phylogenetic utility of the chosen MLST targets.

Main Methods:

• Analysis of 415 STs derived from 2,089 C. trachomatis specimens.
• Incorporation of 49 ompA gene variants to create 459 profiles.
• Utilized eBURST and minimum spanning tree analyses for geographical distribution and variation.

Main Results:

• Identified 415 unique STs and 459 profiles, with specific STs predominating in men who have sex with men (MSM) and heterosexual populations.
• Observed lower genetic diversity in ocular trachoma cases compared to sexually transmitted infections.
• Phylogenetic analysis confirmed MLST targets yield results comparable to whole-genome sequencing.

Conclusions:

• The developed MLST scheme successfully identifies globally prevalent Chlamydia trachomatis strains.
• This MLST approach serves as a valuable tool for epidemiological surveillance and phylogenetic studies.
• No single gene was definitively linked to the successful spread of dominant STs.