A lack of association between BRCA1 mutations and PCa grade is in line with published data [8], [9], and the higher SIR for GS ≤ 6 disease might reflect a higher propensity for diagnosing indolent low-grade tumours that would not have been detected in the absence of the discovery of a deleterious mutation. The gene discussed is BRCA1; the disease is posterior cortical atrophy.