Identifying and testing for hereditary susceptibility to breast / ovarian

About 90% of all breast cancers can be considered as sporadic, without inherited gene alteration. The rest of breast cancers (about 5 to 10%) are considered hereditary, most commonly caused by alterations of BRCA1/2 tumor suppressor genes. Lifetime risks for breast and ovarian cancers are increased among BRCA1/2 mutation carriers – 4 to 8 and 10 to 20 fold higher respectively. Due to the small proportion of hereditary form of disease, as well as to the high cost, BRCA testing is not screening test for general population. It is addressed to selected part of population that fit to recommended criteria. Full coding region sequencing of both genes is “gold standard” for detection of BRCA mutation. Concerning BRCA testing in Serbia, complete or partial sequencing of BRCA1/2 coding region was performed in 60 samples. The presence of 4 BRCA1 known mutations, previously detected elsewhere, has been shown: 185delAG, C61G, 3447del4 and 5382insC (detected twice). In BRCA1 gene, exon 16, an unclassified variant M1652I was found. Polymorphic variants in BRCA1 (8 polymorphisms) and BRCA2 (5 polymorphisms) genes were also detected. The majority of found BRCA1 and BRCA2 polymorphic variants are the missense ones and their influence on breast/ovarian cancer risk in our population has to be proved. Identification of BRCA mutations carriers and establishment of spectra and frequency of BRCA mutations should enable introduction of BRCA1/2 testing into the clinical practice of Serbia.