We used data from the Breast Cancer Family Registry (Breast CFR), a large international consortium that has enrolled more than 13 000 breast cancer families (John et al, 2004), to study cancer risks for close relatives of women (index cases) who had very early-onset breast cancer and had been identified through population-based cancer registries, a large proportion of whom had been screened for mutations in BRCA1 and BRCA2. Here, BRCA1 is linked to cancer.