BRCA1 hereditary cancer pedigree.

This pedigree organizes a family history that may raise questions about hereditary breast and ovarian cancer. It distinguishes family members reported as affected from those known to carry a variant and those who are presymptomatic. The affected proband is marked so the clinical reason for the chart remains clear. Pedigrees are especially useful in cancer-risk assessment because they make relationships, generations and patterns of illness visible at once. A clinician can add ages of diagnosis, primary cancer sites and test results as the history becomes more complete. This is an illustrative chart only. Risk assessment and decisions about genetic testing should be made with an appropriately qualified health professional.