There is still uncertainty as to why BRCA2 families, ascertained on the basis of members with breast and/or ovarian cancer, have a higher RR of prostate cancer in men carrying protein-truncating BRCA2 mutation (BCLC, 1999; Johannsson et al, 1999; Eerola et al, 2001; Tulinius et al, 2002; Bermejo and Hemminki, 2004; van Asperen et al, 2005). This evidence concerns the gene BRCA2 and prostate carcinoma.