BRCA1 AND BRCA2 MUTATIONS IN BELGIAN FAMILIES WITH A HISTORY OF BREAST AND OR OVARIAN/

Certain familial breast and/or ovarian cancers, specially those diagno sed early, are dominantly heritable and have been linked to mutations in BRCA1 and BRCA2 genes. We have tested 30 women selected from 25 dif ferent families with specific criteria. Blood samples were always take n with the informed consent and preliminary interview of the patient b y a physicologist specialized in presymptomatic testing. Mutation dete ction were performed by protein truncation test (PTT), gradient gel el ectrophoresis (DGGE) and subsequent sequencing. The results showed fou r frameshift mutations among which three induced truncation of the BRC A1 protein and one of the BRCA2 protein. One of the BRCA1 mutations an d the only BRCA2 mutation are prevelant among caucasians. Interestingl y, one BRCA1 mutation is shared both by Dutch and French families and another one has not yet been reported. Furthermore, a new unclassified varient was identified. Conclusion: by using specific selection crite ria, we have been able to detect BRCA mutations in four out of the 25 families tested. One of the mutations seems to be found only in Belgiu m. Genetic counselling is being offered to their relatives. (C) 1998 R apid Science Ltd.