Background:

Chlamydia trachomatis is the most frequently identified bacterium in sexually transmitted infections. Twenty C. trachomatis genotypes have been determined using the ompA gene and several genovariants by single nucleotide polymorphism (SNP) analysis. In Mexico, the F genotype is the most frequent.

Objective:

To identify subtypes of the F genotype.

Method:

Seven C. trachomatis genotype F strains isolated in 2011 were analyzed by nucleotide sequencing and restriction enzyme mapping.

Results:

SNP analysis showed two strains with the same SNP at nucleotide 288 (C288T), while with res-triction enzymes, a variant with different RFLP (restriction fragment length polymorphism) was identified when treated with the mixture of HinfI and TaqI enzymes.

Conclusion:

In Mexico, there are two subtypes of F, and only with restriction enzymes HinfI and TaqI can identify one of the genovariants of the F genotype.