BRCA1 and BRCA2 germline mutations in Moroccan breast/ovarian cancer families: novel mutations and unclassified variants.

OBJECTIVE

Breast cancer is the most common female cancer in Morocco. About 5 to 10% are due to hereditary predisposition and mutations in BRCA1 and BRCA2 genes are responsible for an important proportion of high-risk breast/ovarian cancer families. The relevance of BRCA1/2 mutations in the Moroccan population was not studied. The main objective of this study is to investigate the spectrum of BRCA1 and BRCA2 germline mutations in early onset and familial breast/ovarian cancer among Moroccan women.

METHODS

We screened the entire coding sequences and intron/exon boundaries of BRCA1 and BRCA2 genes in 40 patients by direct sequencing.

RESULTS

Nine pathogenic mutations were detected in ten unrelated families, five deleterious mutations in BRCA1 gene and four mutations in BRCA2 gene. Four novel mutations were found: one in BRCA1 (c.2805delA/2924delA) and three in BRCA2 (c.3381delT/3609delT; c.7110delA/7338delA and c.7235insG/7463insG). We also identified 51 distinct polymorphisms and unclassified variants (three described for the first time).

CONCLUSIONS

Our data suggest that BRCA1 and BRCA2 mutations are responsible for a significant proportion of familial breast cancer in Moroccan patients. Therefore full BRCA1/2 screening should be offered to patients with a family history of breast/ovarian cancer.