Prevalence of BRCA1 mutations in breast cancer patients from Argentina.

ALONSO, E.N. ; OROZCO, M.; NIETO, A.E.; FERRONATO, M.J.; LE MOGLIE, M.G.; BARUTTA, E.; VINCENT, E.; FERRO, A.; MARTINEZ, D.; MARTINEZ, I.; MAEGLI, M.I.; KOWALYSZYN, R.; SALVADORI, M.; GINESTET, P.; BALOGH, G.A.

Milan

Congreso; ESGO 2011 - 17th International Meeting of the European Society of Gynaecological Oncology.; 2011

Breast cancer is a leading cancer in Argentina and incidence rate are similar to USA. However the contribution of BRCA1 or BRCA2 to breast cancer incidence in Argentina has not yet been explored. In order to estimate the proportion of breast cancers due to BRCA1 mutations in Argentina, and to identify possible founder mutations, we conducted a study of breast cancer patients. We enrolled 206 women with breast cancer from several Hospitals from Bahia Blanca and its region. A bucal smear sample was obtained by duplicate from each patient. DNA sample was processed for polymorphisms analysis employing single strand conformational polymorphism (SSCP) technique. The alterations of polymorphisms in BRCA1 were sought using a combination of 15 primers to analyze exons 2, 3, 5, 20 and 11 (11 regions). BRCA1 mutations were confirmed by direct sequencing. We were able to successfully complete testing on samples from 115 women. Among these, sixteen mutations were identified in BRCA1 gene representing 13.9% of the samples analyzed. We found one patient with polymorphism in exon 2 (0.86%), four patients with alterations in exon 20 (3.48%), four patients with polymorphisms in exon 11.3 (3.48%), one in exon 11.7 (0.86%), two in exon 11.8 (1.74%), one in exon 11.10 (0.86%) and one in exon 11.11 (0.86%). We observed that the most prevalent alteration in BRCA 1 in our country are located in exon 11 (9 out of 16 patients, 56.25%) in breast cancer patients. Our next objective is to evaluate the prevalence of mutations in BRCA2 gene.