We found that 20 (39%) patients with PCa had prevalent (i.e., >50% mutant) missense or frameshift somatic mutations at both (a) BRCA1 or BRCA2, and (b) POLQ, ATM, ATR, or PARP1. Of these 20 patients, 15 had LOH at BRCA1 or BRCA2 (Supplementary data 1). This evidence concerns the gene PARP1 and posterior cortical atrophy.