The silent mutation nucleotide 744 G → A, Lys172Lys, in exon 6 of BRCA2 results in exon skipping
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Germ-line mutations in BRCA2 predispose to breast and ovarian cancer. Mutations are widespread throughout the gene and include disease-causing mutations as frameshift, nonsense, splicing mutations and large genomic rearrangements. However a large number of mutations, including missense, silent and intron variants are of unknown significance. Here, we describe the functional characterization of a silent mutation (nucleotide 744 G → A/c.516 G → A, Lys172Lys) in exon 6 of BRCA2 in a Danish family with breast and ovarian cancer. Exon trapping analysis showed that the mutation results in skipping of exon 6 and/or both exon 5 and 6, which was verified by RT-PCR analysis on RNA isolated from whole blood of the affected patient. We therefore conclude that the BRCA2 silent mutation Lys172Lys is a disease-causing mutation.
KeywordsBreast cancer BRCA2 Silent mutation Splicing Exon trapping RT-PCR
This study was supported by the Neye Foundation and the Danish Cancer Society.
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