Fig. 2.

Analysis by cBROCA of mutations in BARD1 and ATM leading to multiple abnormal transcripts. (A) In family CF5058, BARD1 c.159-1C>T occurs in the proband, who was diagnosed with ovarian cancer (Ov) at age 58, her son who was diagnosed with prostate cancer (Pr) at age 52, and two other female relatives who underwent risk-reducing bilateral salpingo-oophorectomy (BSO) and remain cancer-free. Heterozygosity for the variant allele is indicated by VN and homozygosity for the nonmutant allele by NN. (B) In family CF1395, ATM c.5674+1G>T occurs in relatives who developed cancers of the breast (Br, including bilateral breast cancer [Bil Br]), ovary (Ov), prostate (Pr), pancreas (Pa), and cholangiocarcinoma/bile duct (Chlnc); and acute lymphocytic leukemia (ALL), leukemia (Leuk), non-Hodgkin lymphoma (NHL), and Hodgkin Disease (HD). Heterozygosity for the variant allele is indicated by VN and homozygosity for the nonmutant allele by NN. (C) In family CF5058, BARD1 c.159-1C>T (black arrow) yields two abnormal transcripts: V1, which skips exon 2, including critical residues Cys53, Cys66, His68, and Cys71 of the BARD1 RING domain, and V2, which skips exons 2 and 3 with an immediate stop at codon 53. Neither of these mutant transcripts appears in controls. (D) In family CF1395, ATM c.5674+1G>T yields multiple abnormal transcripts, nearly all of which (V1 cluster) extend into ATM intron 36 where they are subject to decay. Evidence of these transcripts was detected by cBROCA in RNA from cells treated with puromycin to inhibit nonsense-mediated decay. Other abnormal transcripts skip exons 37 and 38 (V2) or exon 37 (V3), both leading to premature stops.