Screening of a novel BRCA2 mutation by rapid in-house PCR-RFLP Screening al unei noi mutaţii BRCA2 prin tehnică rapidă PCR-RFLP elaborată in-house

Abstract BRCA1 and BRCA2 are major cancer predisposition genes, responsible for a large percentage of heredi-tary breast and ovarian cancer (HBOC) families. The distribution of BRCA mutations has been studied in many populations, though only recently so in Romania. We started the first local oncogenetic study, searching for muta-tions of BRCA genes in HBOC families, by using mutation-specific PCR-based methods and dideoxy sequencing. We investigated 104 samples from familial (29 HBOC) and non-familial cancer cases (50 breast, 25 ovary), from North-Eastern Romania. Among the diversity of BRCA deleterious mutations, a novel BRCA2 mutation in exon 21, c.8680C>T, was identified. The T for C substitution creates a stop codon at position 2894, truncating the last C-ter-minal 525 amino acids of BRCA2 protein. The mutation is not yet stored in international databases. The mutation was firstly identified in a breast cancer predisposition family. We imagined a simple and rapid screening for c.8680C>T identification. This substitution creates an additional TaaI restriction site, allowing a quick identifica-tion of the mutation by PCR-RFLP and agarose gel electrophoresis. Rapid screening allowed the identification of the same mutation in a sporadic ovarian cancer patient. Our results could open the way for a population study to determine the frequency of c.8680C>T, its possible recurrence, and an eventual founder effect in Romania.