TLR2 haplotypes in the susceptibility to and severity of Chlamydia trachomatis infections in Dutch women

Chlamydia trachomatis infections may cause several disease conditions ranging from asymptomatic infections to severe upper genital tract pathology, thereby causing significant morbidity worldwide. Remarkable interindividual differences in the clinical course of C. trachomatis infection have been observed, and are mainly based on variation in genes encoding immune-regulatory and bacteria-sensing proteins. Toll-like receptors (TLRs) are closely involved in pathogen recognition and host defense in C. trachomatis infections. The aim of this study is to assess the role of TLR2 single nucleotide polymorphisms and haplotypes in the susceptibility to, and severity of C. trachomatis infections. The study comprised a sexually transmitted disease cohort of 468 Dutch Caucasian women and a control group of 321 women. The subfertility cohort consisted of 56 women with clinically well-defined tubal pathology. The results showed no significant differences in individual TLR2 genotype frequencies in the susceptibility for C. trachomatis infections between the C. trachomatis-positive group and controls. However, haplotype 1 was statistically significant (P = 0.015) and was associated with protection against tubal pathology following C. trachomatis infection. The same haplotype was also significantly decreased (P = 0.021) in increasing severity of C. trachomatis infections (asymptomatic > symptomatic > tubal pathology) suggesting a protective effect of this haplotype against the development of late complications.