CASE REPORT: HEREDITARY BREAST CANCER AND LARGE REARRANGEMENTS IN PATIENT OF ASHKENAZI ORIGIN

VARGAS AL; VARGAS ROIG LM; MAMPEL A.; GAGP FE; CARDPSP FC; SOLANO AR

Mendoza

Encuentro; XXXVI Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2018

Sociedad de Biología de Cuyo

Hereditary breast cancer represents 5-10% of cases of breast cancer and is mainly associated with mutations in BRCA1 and BRCA2 genes. Patients of ashkenazi Jewish origin have an increase in the prevalence of mutations in these genes, with 90-95% carriers of founder pathogenic mutations in BRCA1/2, while 2-4% carry another type of mutation. To date, there are no reports of large rearrangements in patients of this origin. In our experience, the frequency of mutations produced by large rearrangements is 0.0045% (9/2000). We present the case of a patient of Ashkenazi-Sephardi origin with breast cancer, carrying a pathogenic deletion in the BRCA1 gene. Case: 37 year-old patient with breast cancer and negative hormone receptors. Her mother, of Sephardic origin, presented ovarian cancer at 60 years of age. From a sample of genomic DNA, the BRCA1/2 genes were studied by Next Generation Sequencing (NGS) and Multiple Ligation-dependent Probe Amplification assay (MLPA) for the study of large rearrangements. By sequencing the presence of pathogenic mutation was not detected and by MLPA (probemix P002 MRC Holland®) the heterozygous deletion including exons 23 and 24 of the BRCA1 gene (c.5407-?_(*1_?) Del) was detected. This mutation is reported in the reference bases as pathogenic. It is considered important to find a rearrangement in patients of this ethnic group in our country and the need to study these genes in full form to establish prevention measures, risk reduction and family counseling.