Fig. 1

Results of the analyses of BRCA1 c.4484 + 3A > C. a) Result of fragment analyses of RT-PCR of patient and control. Analysis of RT-PCR products of the patient and control sample showed one fragment with the expected product size in both samples, in addition to one shorter fragment which is only present in the patient sample (top). b) Result of sequencing of fragments from RT-PCR in patient and control. Electropherogram of the sequence of the RT-PCR product from the patient showing a transcript lacking exon 13, in addition to the full length transcript (top). Both samples also show the known alternative transcript, r.4358_4360del, lacking the first three bases of exon 13 (called Δ14 in ENIGMA report by Colombo et al. 2014). c) Results of investigation of biallelic expression. Investigation of biallelic expression using primers specific for amplification of wild type transcript shows monoallelic expression as a pure G appears at position c.4837 in the cDNA (top), compared to the heterozygous pattern in the patient DNA (below). The result indicates that the mutated allele does not produce WT-transcript