Summary The presence of a high nevus number is the strongest phenotypic predictor of melanoma risk. Here, we describe the results of a three-stage study directed at identifying risk variants for the high nevus phenotype. At the first stage, 263 melanoma cases from Barcelona were genotyped for 223 single-nucleotide polymorphisms (SNPs) in 39 candidate genes. Seven SNPs in the PAX3 gene were found to be significantly associated with nevus number under the additive model. Next, the associations for seven PAX3 variants were evaluated in 1217 melanoma cases and 475 controls from Leeds; and in 3054 healthy twins from TwinsUK. Associations with high nevus number were detected for rs6754024 (P values