RESUMO
PURPOSE: Pathogenic/likely pathogenic (P/LP) germline variations in BRCA1 and BRCA2 genes are responsible for the majority of hereditary breast and ovarian cancers. This study presents the BRCA1/BRCA2 sequencing and deletion duplication analyses results of of 493 participants (485 women, 8 men) selected based on the National Comprehensive Cancer Network (NCCN) guidelines. METHODS: Next generation sequencing (NGS) and multiplex ligation-dependent probe amplification methods (MLPA) were used to define germline BRCA1/BRCA2 positivity. RESULTS: Overall, the P/LP frequency of the participants was 17.8%. Five of the likely pathogenic variants were novel. The 5266dupC pathogenic variation, which is a founder mutation in the Ashkenazi Jewish population, was the most common variation among the patients, with a frequency of 5.47%. The pathogenic/likely pathogenic variation frequency was significantly higher (p=0.01) among clinically diagnosed familial cancer patisents than those participants without personal history of cancer but enrolled for BRCA1 testing due to familial risk. BRCA1/BRCA mutation positivity was significantly higher (p=0.000) among those who had at least one first- or second-degree relative with breast/ovarian cancer from patients who had no family history. BRCA1/BRCA2 mutation positivity was 69.23% between the patients who had personal history of both breast and ovarian cancer. CONCLUSION: Based on our findings, we suggest that sequencing all of the coding regions of the BRCA1/BRCA2 genes using NGS is a feasible approach for individuals who are at risk of developing BRCA-related cancer according to NCCN guidelines. The 5266dupC pathogenic variation, as the most common pathogenic variation in the Trakya region of Turkey, should be included if a targeted mutatin screening is planned.
Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética , Mama/patologia , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/genética , Detecção Precoce de Câncer/métodos , Feminino , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Linhagem , TurquiaRESUMO
The cytochrome P450 2D6 (CYP2D6) is a cytochrome P450 enzyme involved in the oxidative biotransformation of the xenobiotics, carcinogens and various clinically important drugs. Patients are evaluated in three sub-groups of extensive (EM), intermediate (IM) and poor metabolizer (PM) phenotypes due to their drug-metabolising ability for the target CYP2D6 gene. Colchicine non-responsive FMF patients were prospectively genotyped for the major CYP2D6 alleles in the current study. Major CYP2D6 alleles of *1, *3, *4, *5, and *6 were genotyped for 30 responsive and 60 non-responsive FMF patients by multiplex PCR-based reverse-hybridization StripAssay and real-time PCR methods. DNA banks isolated from blood-EDTA were retrospectively used in the current patients and results were compared statistically. Increased CYP2D6 *4 and *6 allele frequencies were highly detected in the colchicine non-responsive FMF patients when compared to the responsive group. Results showed the frequencies of major CYP2D6 *1(wild), *3(2637A > delA), *4(G1934A), *5(total gene deletion) and *6(1707T del) alleles in 0.550, 0.042, 0.158, 0.025 and 0.225 for non-responder and 0.880 and 0.120 (CYP2D6*1 and *4) for the responder groups, respectively. Despite small sample size, this study suggests that there is an association between CYP2D6*4 and CYP2D6*6 alleles and drug intoxicants in colchicine non-responder FMF patients.