Rolf Sijmons has worked as a clinical geneticist in the field of oncogenetics for more than 20 years. He is Associate Professor of Clinical Oncogenetics at the University Medical Center Groningen, the Netherlands, and leads the familial cancer clinic at his department. His research interests mainly focus on the genetics of colorectal cancer, the clinical interpretation of unclassified variants, and bioinformatics tools to support clinical management of cancer families. He is member of several international committees in these fields and is editor of the familial cancer database.