RESUMO
BACKGROUND: Retinoblastoma (Rb) is the most prevalent intraocular pediatric malignancy of the retina. Significant genetic factors are known to have a role in the development of Rb. METHODS: Here, we report the mutation status of 4813 clinically significant genes in six patients with noncarrier of RB1 gene mutation and having normal RB1 promoter methylation from three families having higher risk for developing Rb in the study. RESULTS: A total of 27 variants were detected in the study. Heterozygous missense variants c.1162G > A (p.Gly388Arg) in the FGFR4 gene; c.559C > T (p.Pro187Ser) in the NQO1 gene were identified. The family based evaluation of the variants showed that the variant, c.714T > G (p.Tyr238Ter), in the CLEC7A gene in first family; the variant, c.55C > T (p.Arg19Ter), in the APOC3 gene and the variant, c.1171C > T (p.Gln391Ter), in the MUTYH gene in second family; and the variant, c.211G > A (p.Gly71Arg), in the UGT1A1 gene in the third family, were found statistically significant (p < 0.05). CONCLUSION: This study might be an important report on emphazing the mutational status of other genes in patients without RB1 gene mutations and having high risk for developing Rb. The study also indicates the interaction between the retinoic acid pathway and Rb oncogenesis for the first time.
Assuntos
Exoma/genética , Predisposição Genética para Doença/genética , Neoplasias da Retina/genética , Retinoblastoma/genética , Adulto , Criança , Pré-Escolar , DNA Glicosilases/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Glucuronosiltransferase/genética , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Mutação de Sentido Incorreto , NAD(P)H Desidrogenase (Quinona)/genética , Linhagem , Regiões Promotoras Genéticas , Mapas de Interação de Proteínas , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Retina , Proteínas de Ligação a Retinoblastoma/genética , Tretinoína/metabolismo , Ubiquitina-Proteína Ligases/genéticaRESUMO
OBJECTIVE: The current rearrangement ratio of BRCA1 and BRCA2 genes is not known in the Turkish population. Rearrangements are not routinely investigated in many Turkish laboratories. This creates problems and contradictions between clinics. Therefore, the aim of this study was to evaluate the distribution and frequency of rearrangements in BRCA1 and BRCA2 genes in high-risk families and to clarify the limits of BRCA1 and BRCA2 testing in Turkey. MATERIALS AND METHODS: The study included 1809 patients at high risk of breast cancer or ovarian cancer. All patients were investigated for both small indels and rearrangements of BRCA genes using DNA sequencing and multiplex ligation-dependent probe amplification (MLPA) analysis. RESULTS: The overall frequency of rearrangements was 2% (25/1262). The frequency of rearrangements was 1.7% (18/1086) and 4% (9/206) in patients with breast cancer and ovarian cancer, respectively. The frequency of rearrangements was 3.7% (8/215) in patients with triple-negative breast cancer. The rearrangement rate was 7.7% (2/26) in patients with both breast and ovarian cancer. CONCLUSIONS: Rearrangements were found with high rates and were strongly associated with bilateral and triple-negative status of patients with breast cancer, which are signs of high risk for breast and ovarian cancer. Analysis of rearrangements should definitely be included in routine clinical practice in Turkey for high-risk families and also for improved cancer risk prediction for families.