Determination of the BRAF V600E mutation in melanomas of Uruguayan patients
Abstract
Introduction: identifying genetic changes that occur in melanoma genesis has enabled the development of therapies that are specifically geared against such changes, what resulted in an increase of patients' survival for the first time in the history of systemic treatment of melanoma, in patients with advanced disease. The best results have been obtained with vemurafenib, a therapy that targets the BRAF protein and is only effective in the presence of the V600E mutation. Thus, its frequency in a certain population measures its potential impact in health figures.
Objective: to evaluate the frequency of the V600E mutation in BRAF in melanomas of Uruguayan patients.
Method: 28 samples of microdissected melanoma were studied and V600E mutation was tested through ASO-PCR (allele specific oligonucleotide - polymerase chain reaction).
Results: we managed to amplify DNA in 27 out of the 28 samples and the mutation was identified in 21 of them (FR: 0.78).
Discussion: previous works demonstrated a lower presence of melanomas that are carriers of the V600E mutation of BRAF (40%-60% in the Caucasian population and 25% in the Asian population) than what our study revealed. Our results, in spite of the need to include a larger number of patients, could partially be due to differences in the technique used and maybe as a consequence of a different proportion of patients with melanomas associated to the intermittent sun exposure.
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