Approximately 30 years ago, when I was in oncology at the Children's Hospital in Philadelphia, a father and a son walked into my office and they both had their right eye missing, and as I took the history, it became apparent that the father and the son had a rare form of inherited eye tumor, retinoblastoma, and the father knew that he had passed that fate on to his son.
Acum 30 de ani, când eram la cabinetul de oncologie  de la Spitalul de Copii din Philadelphia, un tată a venit la mine la cabinet cu fiul său. Ambii aveau ochiul stâng extirpat. Am cercetat și am aflat că amândoi aveau o formă rară de cancer ocular moștenită, retinoblastom. Tatăl știa că o transmisese fiului.