Association of COX2 functional polymorphisms and the risk of vitiligo in Chinese populations.

BACKGROUND

Cyclooxygenase-2 (COX2) plays an important role in the production of prostaglandin E2 (PGE2), which is made by epidermal keratinocytes in response to ultraviolet radiation (UVR). PGE2 is important for the proliferation and melanogenesis of epidermal melanocytes, the loss of which leads to vitiligo. COX2-1195A>G, -765G>C, and -8473T>C polymorphisms may influence the mRNA levels of COX2 and affect the production of PGE2 subsequently. Therefore, we supposed that these polymorphisms may be associated with vitiligo.

OBJECTIVE

The aim of the study was to elucidate the association between three functional COX2 polymorphisms and the risk of vitiligo.

METHODS

This was a hospital-based, case-control study of 755 vitiligo patients and 774 vitiligo-free controls who were frequency matched by age and sex. We genotyped COX2-1195A>G, -765G>C, and -8473T>C polymorphisms by using PCR-restriction fragment length polymorphism (RFLP) method and assessed their respective associations with the risk of vitiligo in Han Chinese populations.

RESULTS

We found a statistically significant increased risk of vitiligo to be associated with the COX2-1195 G variant allele (p=0.004). Significantly higher vitiligo risks were found among subgroups with these characteristics: age >20 years, male, active, nonsegmental vitiligo, and onset age >20 years. In addition, the interaction between COX2-1195 and COX2-8473 was statistically significant (p=0.004).

CONCLUSION

For the first time, we provide evidence that functional polymorphisms in the COX2 gene may influence the risk of vitiligo in Han Chinese populations, suggesting new clues that help to clarify the pathogenesis of vitiligo. Larger studies are needed to verify these findings.