The observation that HsRAD52-S346X both protects against breast cancer in carriers of pathogenic BRCA2 mutations [30], and confers a loss of HsRAD52-dependent DSB repair by HRR in budding yeast cells suggests that a similar DNA repair defect may contribute to the synthetic lethality thought to promote the protective effect in humans. This evidence concerns the gene BRCA2 and breast carcinoma.