Abstract B53: BRCA1 and BRCA2 mutations spectrum in Puerto Rican Hispanics

Abstract

Abstract Introduction: Hereditary breast cancer accounts for up to 10% of breast cancer cases. These hereditary breast cases have been shown to be associated with mutations in the BRCA1 and BRCA2 genes. The prevalence and types of mutations in these genes varies depending on the population and ethnicity under study. Identification of such specific mutations allows for site specific testing. In the absence of knowledge of specific mutation information, entire gene sequencing is necessary in order to identify the putative mutations involved in the predisposition to increased risk. Objective: The objective of this project is to identify and annotate the mutations in BRCA1 and BRCA2 genes encountered in the Puerto Rican population which will allow for accessible genetic testing services to be offered. Methods: From January 2014 to May 2016, we recruited 46 women that met the National Comprehensive Cancer Network guidelines for breast cancer genetic testing. Among recruited participants, 18 were diagnosed with breast cancer, 8 with ovarian cancer, 1 with both breast and ovarian cancer and 19 had family history of breast or ovarian cancer suggestive of hereditary cancer. The recruited individuals were submitted to genetic testing, first by the Hispanel breast cancer mutation panel, developed at City of Hope Division of Clinical Cancer Genetics. If negative on the Hispanel, Sanger sequencing was performed to evaluate the whole genes and confirm results. Results: Our results showed 38 negative genetic testing for BRCA1/BRCA2, 4 variants of uncertain significance and 4 pathogenic mutations in the population under study. One pathogenic mutation was found in BRCA1 (BRCA1 exon15-16del) and 3 pathogenic mutations were found in BRCA2 (BRCA2 2022del5; BRCA2 4150G>T (E1308X); BRCA2 6027del4). Conclusion: The prevalence of mutations in this preliminary study is consistent with previous reports of BRCA mutations in Puerto Rico, which describe as BRCA2 as the most commonly mutated gene in the island. Additional studies are needed to fully elucidate the BRCA1/BRCA2 mutation spectrum in Puerto Rico for allowing the implementation of cost-effective and affordable genetic testing strategies for women in need. Citation Format: Julyann Pérez-Mayoral, Adrian Cora-Morges, Krystel Gonzalez-Rosa, Jessica Hernandez, Danielle Castillo, Josef Herzog, Jeffrey Weitzel, Marcia Cruz-Correa. BRCA1 and BRCA2 mutations spectrum in Puerto Rican Hispanics. [abstract]. In: Proceedings of the Ninth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2016 Sep 25-28; Fort Lauderdale, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(2 Suppl):Abstract nr B53.