The study aims at investigating the progression from nevi to melanoma in a cross sectional study of melanoma cases from Mediterranean countries. The study will focus on the comparison of gene expression and proteomics profile in normal skin, common melanocytic nevi, dysplastic nevi, and melanoma tissue samples from the same individuals. Genotype analysis on melanoma candidate genes will also be performed in these subjects, and compared with the gene expression and protein profiles. Each subject will complete an interview-based questionnaire on sun exposure, pigmentation, sun-sensitivity, family and medical history, and other melanoma risk factors and donate a blood sample. A single dermatologist will examine every patient to reveal skin lesions and phenotypic characteristics associated with pigmentation. Further, any skin lesion of interest will be photographed and stored with the correspondent pathological record.