Frameshift: predicted to result in premature termination within exon 11 (p.233X). However, this mutation occurs in an exon that is absent in the predominant, in-frame, naturally occurring isoform Δ9,10 and may be spliced out to produce a partially functional protein (47). RT-PCR analysis suggested increased nonsense-mediated mRNA decay. LOH analysis on genomic DNA from P2’s tumour showed no LOH at either BRCA1 allele – suggesting that both mutated alleles are dysfunctional (30). Here, BRCA1 is linked to neoplasm.