Almost 200 Children Born From Donor Carrying Deadly Cancer Gene

A major investigation has discovered a deeply troubling case where at least 197 children across Europe were conceived using sperm from a donor who unknowingly carried a dangerous TP53 gene mutation linked to extremely high cancer risk. Some of the children have already developed cancer, multiple have faced two different cancers, and a few have tragically died.The donor began giving sperm as a student in Denmark in 2005, and his samples were used for around 17 years across clinics in 14 countries. While he is healthy and passed all routine screenings, a spontaneous DNA mutation occurred before he was born, affecting the TP53 gene in a small proportion of his cells. Up to 20% of his sperm carried the mutation, which is associated with Li-Fraumeni

syndrome, a condition that can result in an up to 90% lifetime risk of cancer — from childhood cancers to bone, brain and breast tumours.

The European Sperm Bank, which distributed his samples broadly, acknowledged that usage limits were breached in several countries. In Belgium, for example, the donor’s sperm was used by 38 women, resulting in 53 children, far above the country’s limit of six families per donor. While the sperm was not sold to UK clinics, a “very small number” of British women travelled to Denmark for treatment and have since been informed.Doctors first noticed the alarming pattern earlier this year at the European Society of Human Genetics, when clinicians treating children with unexplained cancers realised they shared the same donor. Follow-up investigations revealed dozens carrying the same mutation.Families now face lifelong medical challenges. Children who inherited the mutation require annual full-body and brain MRIs, abdominal ultrasounds, and long-term monitoring. Women with the mutation often choose preventive mastectomies to lower breast-cancer risk. As one mother, Céline, said, she has “absolutely no hard feelings” toward the donor but is devastated to learn her daughter lives under a constant threat: “We don’t know when, we don’t know which one, and we don’t know how many.”

Experts say this case exposes a dangerous gap in international fertility regulation. There is no global limit on how often a donor’s sperm can be used, even as international sperm banks now supply half of the UK’s imported sperm. As Prof Allan Pacey argues, “You can’t screen for everything” — but without global oversight, families may pay the highest price.