Fig. 6.

TINS are increased in tumors with high POLQ expression and with BRCA mutations. (A and B) Number of insertions with templated synthesis 5 bp or more per tumor (TINS/tumor, defined as in Fig. 4A) for breast cancer genomes previously sequenced by ICGC were determined according to differing POLQ mRNA expression level (A) or BRCA1 or BRCA2 germline status (B). (A) POLQ expression in fragments per kilobase of transcript per million was normalized based on HPRT1, TBT, and GAPDH expression for 261 breast cancers. Tumors were categorized as expressing low (POLQ low; bottom quartile) or high levels of POLQ mRNA (POLQ high; top quartile). Statistical significance was assessed with a two-tailed Mann–Whitney U test; *P < 0.05. (B) Breast cancers were categorized as having germline BRCA1 or BRCA2 mutations (mutant, 75 cancers) or not (WT, 494 cancers).