Sperm Donor Cancer Mutation Affects Nearly 200 Children Across Europe
An international investigation has revealed that a single sperm donor carrying a rare genetic mutation linked to cancer fathered almost 200 children across Europe, putting dozens at high risk of developing life-threatening disease.
Investigation Uncovers High-Risk Genetic Mutation
Scale of the Case
A dangerous genetic mutation carried by one anonymous sperm donor has affected nearly 200 children over 17 years. The donor, who began donating sperm in 2005 while a university student, unknowingly carried a mutation that dramatically increases the risk of cancer. The investigation, conducted by 14 public broadcasters including the BBC, found that several children conceived with his sperm have already developed cancer. Some have died, while others face a lifetime cancer risk of up to 90 percent.
Mutation Details
The mutation impacts the TP53 gene, which prevents cells from becoming cancerous. While most of the donor’s own cells are healthy, experts estimate that around 20 percent of his sperm carried the mutation due to a spontaneous genetic change before his birth. Children conceived with affected sperm inherit the mutation in every cell of their body. This condition is associated with Li-Fraumeni syndrome, a rare disorder that increases the risk of aggressive childhood cancers and, for women, breast cancer later in life.
European Sperm Bank Admits Failures
Oversupply of Donor Sperm
The European Sperm Bank, based in Denmark, supplied the donor’s sperm to 67 fertility clinics in 14 countries. The bank expressed “deepest sympathy” to affected families and admitted the donor’s sperm was used too widely, breaking recommended limits. Regulations differ by country. In Belgium, one donor should serve no more than six families, yet this donor fathered 53 children for 38 women. In the UK, the limit is 10 families, and although no batches were sent to UK clinics, some British women traveled to Denmark for treatment and were only recently informed of the genetic risk.
Early Medical Findings
Among 67 children born by early 2025, 23 carry the TP53 mutation, and ten have already been diagnosed with cancer. Some children developed more than one type of cancer, while others died at a young age. Experts describe the situation as “heartbreaking” and warn that routine screening rarely identifies such mutations, making early detection extremely difficult.
Calls for Tighter Global Sperm Donation Rules
Health and Emotional Risks
The case has intensified calls for stricter international limits on how often a single sperm donor can be used. Reproductive health groups highlight medical risks and emotional challenges for children discovering they are part of a large group of half-siblings.
Families Speak Out
Several families are demanding a full review of fertility regulations. Many live with constant uncertainty, knowing the threat of cancer may arise at any time. A mother in France said she feels like she is “standing in the shadow of a possible cancer every day.” “We don’t know when it will happen, what kind it will be, or how often it might return,” she added. “But we will face it whenever it appears.”
