BRCA1 and BRCA2 genes mutation analysis in patients with a family history of breast and ovarian cancer

Abstract

Hereditary breast and ovarian cancer syndromes can be caused by loss-of-function germline mutations in one of the tumor suppressor genes BRCA1 and BRCA2. In order to characterize these mutations in the Greek population we have been collecting samples from breast/ovarian cancer patients with a family history in collaboration with a large number of Greek Hospitals. Our DNA bank contains samples from more than 300 patients, corresponding to approximately 250 families. In terms of family history this group consists of three subgroups: (I) very early onset (<30 yrs) without family history (10%); (II) moderate family history (2 members affected, < 50 yrs) (40 %) (III) strong family history (3?7 members affected) (50 %). Screening of BRCA1 and BRCA2 genes in 150 patients has revealed deleterious mutations in 39 unrelated patients. 5382insC has been found in 11 unrelated families. In summary, the mutation spectrum of BRCA1 and BRCA2 genes in the Greek population seems to be composed by an elevated frequency of 5382insC with the rest being novel or recurrent mutations with low frequency in both genes. Screening of BRCA1 gene is also in progress in collaboration with the Institute of Oncology and Radiology of Serbia. DNA samples have been collected from 32 Serbian families with a family history of breast ovarian cancer. Direct sequencing in exons 2, 5 and 20 of all these samples revealed only one deleterious mutation (C61G) in exon 5 of BRCA1 gene. Screening of the remaining exons is in progress.