EGF +61 gene polymorphism and susceptibility to and prognostic markers in cutaneous malignant melanoma

Abstract

CMM is the most serious cutaneous malignancy and is increasing in frequency among most Caucasian populations, where the most important risk factor is exposure to UV light. Relatively little is known of the genetic factors that mediate susceptibility to and prognosis in sporadic CMM, although a number of genes have been implicated. A striking association between EGF polymorphism and Breslow thickness of invasive CMM has been reported. We have sought confirmation of this finding in an independent study of 159 patients and 310 controls using TaqMan fluorescence-based genotyping for EGF +61. In our study group, there were no significant differences in EGF genotype frequencies between patients and controls nor was EGF genotype associated with tumour growth phase, stage or mitotic count. However, correlation between EGF genotype and Breslow thickness showed a modestly significant increase in frequency of the EGF (G/G) genotype among tumours >3.5 mm thick (30.0% vs. 9.8%, p = 0.03). In summary, in our group, the EGF +61 polymorphism was not a risk factor for CMM susceptibility, but this polymorphism may play a role in disease progression.