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At present, breast cancer is the most common type of cancer in females. The majority of cases are sporadic, but 5-10% are due to an inherited predisposition to develop breast and ovarian cancers, which are transmitted as an autosomal dominant form with incomplete penetrance. The beneficial effects of clinical genetic testing, including next generation sequencing (NGS) for BRCA1/2 mutations, is major; in particular, it benefits the care of patients and the counseling of relatives that are at risk of breast cancer, in order to reduce breast cancer mortality. BRCA genetic testing was performed in 15 patients with breast cancer and a family with positivity for the heterozygous c.6428C>A mutation of the BRCA2 gene. Informed consent was obtained from all the subjects. Genomic DNAs were extracted and the NGS for genes was performed using the Ion Torrent Personal Genome Machine (PGM) with a 316 chip. The reads were aligned with the human reference HG19 genome to elucidate variants in the BRCA1 and BRCA2 genes. Mutations detected by the PGM platform were confirmed by target direct Sanger sequencing on a second patient DNA sample. In total, 4 BRCA variants were identified in 6 families by NGS. Of these, 3 mutations had been previously reported: c.2126insA of BRCA1, and c.1310_1313delAAGA and c.7235insG of BRCA2. The fourth variant, c.3453delT in BRCA1, has, to the best of our knowledge, never been previously reported. The present study is the first to apply NGS of the BRCA1 and BRCA2 genes to a Moroccan population, prompting additional investigation into local founder mutations and variant characteristics in the region. The variants with no clear clinical significance may present a diagnostic challenge when performing targeted resequencing. These results confirm that an NGS approach based on Ampliseq libraries and PGM sequencing is a highly efficient, speedy and high-throughput mutation detection method, which may be preferable in lower income countries. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer affecting women all over the world. The World Health Organization estimated that 1.38 million breast cancers were diagnosed worldwide in 2008. In Morocco, according to the Greater Casablanca Cancer Registry, breast cancer seems to be the first female cancer with a standardized incidence of 36.4 for an average age of 49.5 years. Germline mutations that inactivate BRCA1 and BRCA2 are responsible for breast and ovarian cancer susceptibility. The prevalence of BRCA1 and BRCA2 mutations where family history shows more than one occurrence of breast cancer under the age of 50 ranges from 8 to 21.2%. High throughput methods such as next generation sequencing are increasingly used in molecular diagnosis. Massive parallel sequencing allows the generation of millions of DNA sequences in a single run with low cost per base. Recently, next generation sequencing methods for the mutation analysis of the BRCA1 and BRCA2 genes in patients with breast and ovarian cancer have been described using both high capacity and bench top platforms. We utilized a workflow using the Ion Torrent Personal Genome Machine (IT-PGM; Life Technologies) an NGS platform, to screen germline mutations in BRCA1 and BRCA2 genes using the Ion AmpliSeq BRCA1 and BRCA2 Community Panel (Life Technologies). Till now, 16 breast cancer patients, considered being at high risk, due to medicinal examination were selected for molecular genetic testing of BRCA1 and BRCA2 genes. Mutations detected by IT-PGM platform were confirmed by traditional mutation detection assay Sanger sequencing. We show that the IT-PGM platform is sensitive and specific and can be used for routine mutational screening of patient with hereditary breast and ovarian cancers. [ABSTRACT FROM AUTHOR]