Transcriptional profiling of melanocytes from patients with vitiligo vulgaris

Vitiligo is a complex, polygenic disorder characterized by patchy loss of skin pigmentation due to abnormal melanocyte function. Both genetic and environmental etiological factors have been proposed for vitiligo and lack of molecular markers renders difficulties to predict development and progression of the disease. Identification of dysregulated genes has the potential to unravel biological pathways involved in vitiligo pathogenesis, facilitating discovery of potential biomarkers and novel therapeutic approaches. In this study, we characterized the transcriptional profile of melanocytes from vitiligo patients. Oligonucleotide microarrays containing similar to 16 000 unique genes were used to analyse mRNA expression in melanocytes from vitiligo patients and age-matched healthy controls. In total, 859 genes were identified as differentially expressed. A substantial number of these genes were involved in (i) melanocyte development, (ii) intracellular processing and trafficking of tyrosinase gene family proteins, (iii) packing and transportation of melanosomes, (iv) cell adhesion and (v) antigen processing and presentation. In conclusion, our results show a significantly different transcription profile in melanocytes from vitiligo patients compared with controls. Several genes of potential importance for the pathogenesis and development of vitiligo were identified. Our data indicate that autoimmunity involving melanocytes may be a secondary event in vitiligo patients caused by abnormal melanocyte function.