BRCA1 and ovarian cancer: Hereditary cancers are by far more common than “classical” genetic diseases: for example, population frequency of breast or ovarian cancers associated with BRCA1/2 gene defects approaches to 1:500 and even reaches 1:50 in some founder populations (Satagopan et al., 2001; Risch et al., 2006; Foulkes et al., 2016), while the most known non-cancer hereditary syndromes, e.g., cystic fibrosis or phenylketonuria, are less frequent at least by an order of magnitude (Strausbaugh and Davis, 2007; Berry et al., 2013).