ABSTRACT
BACKGROUND: Mutations in BRCA1 and BRCA2 are well-established risk factors for breast and ovarian cancer. In Central-Eastern European counties, the founder mutations in the BRCA1 are responsible for a significant proportion of ovarian cancer cases, however, regional differences in the frequencies of various mutations may exist. The spectrum and frequency of BRCA1/2 mutations between ovarian cancer patients have not yet been precisely established in Belarus. METHODS: Two hundred fourteen consecutive unselected cases of ovarian cancer patients from the region of West Belarus were examined. We studied 13 founder mutations in BRCA1 (c.5266dupC, c.4035delA, c.5251C > T, c.181 T > G, c.676delT, c.68_69delAG, c.3700_3704delGTAAA, c.1687C > T, c.3756_3759delGTCT) and in BRCA2 (c.658_659delGT, c.7913_7917delTTCCT, c.3847_3848delGT, c.5946delT) characteristic for Central European population. RESULTS: A BRCA1 or BRCA2 founder mutations were detected in 54 of the 214 (25.2%) ovarian cancer cases. The BRCA1 c.5266dupC mutation was detected in 28 patients, followed by c.4035delA mutation observed in 18 patients. BRCA1 c.3756_3759delGTCT, c.68_69delAG, and c.1687C > T were found in 3, 2, and 1 women, respectively. BRCA2 c.658_659delGT mutation was detected in 2 ovarian cancer patients. The median age of diagnosis of the 54 hereditary ovarian cancers was 57.5 years. CONCLUSIONS: The frequency of 13 causative BRCA1 and BRCA2 founder mutations in West Belarus was higher than in other Slavic countries. Testing of BRCA1 (c.5266dupC, c.4035delA, c.3756_3759delGTCT, c.68_69delAG, c.1687C > T as well as c.181 T > G) and BRCA2 (c.658_659delGT) mutations should be considered an inexpensive and sensitive test panel for this population.
ABSTRACT
In Belarus and other Slavic countries, founder mutations in the BRCA1 gene are responsible for a significant proportion of breast cancer cases, but the data on contribution of these mutations to ovarian cancers are limited. To estimate the proportion of ovarian cancers in Belarus, which are dependent on BRCA1 Slavic founder mutations, we sought the presence of three most frequent mutations (BRCA1: 5382insC, C61G and, 4153delA) in 158 consecutive unselected cases of ovarian cancer. One of the three founder mutations was present in 25 of 158 unselected cases of ovarian cancer (15.8 %). We recommend that all cases of ovarian cancer in Belarus be offered genetic testing for these founder mutations. Furthermore, genetic testing of the Belarusian population will provide the opportunity to prevent a significant proportion of ovarian cancer.
