Turkish population-based screening for first identified changes of BRCA1 and BRCA2 genes in breast and/or ovarian cancer patients

Abstract

It is known that BRCA1 and BRCA2 genes’ mutation carriers are predisposed to breast and ovarian cancers and other organ cancers such as prostate, colon and cervix. In the previous study performed at X University, all coding exons of both genes were screened by denaturing gradient gel electrophoresis (DGGE). In addition to various nonsense, missense mutations, polymorphisms and intronic region changes, seven novel missense mutations, including H513L, H816P and S1517Y in BRCA1 and S326R, G258P, E2903K and N2742S in BRCA2, had been identified. To determine whether these unclassified variants are pathogenic, DNA samples of 150 healthy individuals without a known cancer history in the family were screened in this study for these seven novel missense mutations. These DNA samples were recruited from archives of previous polymorphism studies. PCR performed DNA amplifications, and denaturing high-performance liquid chromatography (DHPLC) techniques did mutation screenings. Peak patterns suggestive of a change in DNA fragments were considered for sequencing analyses. Analyses revealed that none of the 150 DNA samples had any change in the seven screened fragments. As a result, it is assumed that these seven mutations might be novel pathogenic mutations described in the Turkish population. In conclusion, these carriers must be informed about the mutation and given appropriate genetic counseling by their physicians. In addition, genetic testing must be offered to high-risk individuals (men/women) in the family so that it would be possible for other family members to have genetic counseling and contribute to disease prevention. On the other hand, these findings would contribute to current literature with novel results and shed light on future research.