Investigating the link between toll-like receptor 9 gene variants and vitiligo susceptibility - A cross-sectional comparative study

Background The Toll-like receptor (TLR) family, which recognises diverse molecular patterns on immune cells, has been implicated in several autoimmune diseases, including vitiligo. Objectives This study will investigate the potential association between the TLR9 gene polymorphism rs187084 and clinical features in Egyptian vitiligo patients, employing the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method for TLR9 genotyping. Methods Genomic DNA was extracted from the peripheral blood of 30 vitiligo patients and 20 healthy controls using a DNA isolation kit. TLR9 rs187084 gene polymorphisms were assessed using PCR-RFLP techniques. Genotype distributions and allele frequencies were compared between vitiligo patients and controls. Additionally, the associations between TLR9 single nucleotide polymorphism (SNP) genotypes and clinical features including demographic characteristics, family history, disease onset, activity, duration, and hair involvement in vitiligo patients were statistically analysed. Results The CC genotype of rs187084, which is considered protective, was found to be more prevalent in the control group compared to the vitiligo group. However, no significant associations were identified between TLR9 SNP genotypes and demographic or clinical parameters, including family history, disease onset, activity, duration, and hair involvement (leukotrichia) in vitiligo patients. Limitation The limitations of this study include a small sample size and the methodological constraints of PCR-RFLP, necessitating further research to confirm our findings and elucidate underlying mechanisms. Conclusions The significant difference in the distribution of the TLR9 rs187084 polymorphism between vitiligo patients and controls highlights the potential role of innate immunity in the susceptibility to vitiligo. Despite the absence of significant associations with clinical parameters in this study, these findings underscore the importance of genetic factors in the pathogenesis of vitiligo.