BRCA1 and breast cancer: The highest mutation frequencies were reported in 30/516 (5.8%) BRCA1/2-negative familial breast cancer patients from Germany [41], 10/172 (5.8%) Ashkenazi Jewish familial BRCA1/2-founder mutation-negative breast and/or ovarian cancer patients or unaffected women [45], 8/89 (8.9%) familial breast cancer patients from the UK, North America and the Netherlands [46] and in 10/82 (12.2%) familial BRCA1/2-founder mutation-negative breast and/or ovarian cancer patients from Finland [27].