Sperm donor with cancer-causing gene fathered 197 children in Europe, reveals investigation

An investigation has revealed that a sperm donor carrying a rare, aggressive cancer-causing gene mutation unknowingly fathered at least 197 children across Europe. The mutation resulted in some of the children developing cancer, and some have died at early age. It wasn't detected during screening because it was a rare, previously unknown variant that wasn't part of standard genetic tests.