Sperm Donor With TP53 Cancer Mutation Fathered Nearly 200 Children Across Europe, Investigation Finds

London — Sperm from a donor who unknowingly carried a cancer-causing mutation in the TP53 gene has been used to conceive nearly 200 children across Europe, an investigation by 14 European public service broadcasters, including BBC News and CBS News partners, has found.

Geneticists warn that some children conceived with that sperm have already died from cancer and that many who inherit the mutation will face a markedly increased lifetime risk of cancer. The mutation causes Li-Fraumeni syndrome, a hereditary condition associated with a high risk of multiple cancers often beginning in childhood.

What Happened

The donor passed routine screening before providing samples to the European Sperm Bank in Denmark while he was a student in 2005. Laboratory analysis suggests up to 20% of his sperm carried the mutated TP53 gene, meaning any child conceived from affected sperm would inherit the mutation in every cell of their body.

"It is a dreadful diagnosis," cancer geneticist Clare Turnbull told the BBC. "It's a very challenging diagnosis to land on a family. There is a lifelong burden of living with that risk. It's clearly devastating."

How The Link Was Discovered

Clinicians treating children with cancers linked to donor conception raised concerns at the European Society of Human Genetics meeting earlier this year. At that point, investigators had identified 23 children who carried the mutation among 67 children traced to the donor; 10 of those children with the mutation had already been diagnosed with cancer.

Subsequent Freedom of Information requests by journalists across several countries indicated the donor's samples had been used to conceive at least 197 children. Authorities caution that more affected children may be identified as clinics and registries review records and genetic data.

"We have some children that have developed already two different cancers and some of them have already died at a very early age," said Edwige Kasper, a cancer geneticist at Rouen University Hospital in France.

Distribution And Regulatory Gaps

The European Sperm Bank sold the donor's samples to 67 fertility clinics in 14 countries. While many countries limit how often a single donor's sperm can be used domestically, there is no international cap on the total number of conceptions from a single donor, a regulatory gap that allowed widespread distribution.

Investigators say national limits appear to have been breached in some places. For example, in Belgium—where rules restrict sperm from one donor to use by a maximum of six families—the probe found 53 children born to 38 different women using sperm from this donor.

Implications And Next Steps

The case has raised urgent questions about donor screening, the need for international registries or limits, and how fertility clinics track and notify recipient families when genetic risks are identified. Medical experts emphasize the importance of genetic counseling for families known or suspected to carry the mutation.

The European Sperm Bank told CBS News it does not ship to the United States because of U.S. regulations and that it works with sperm banks in Canada and Mexico. Investigations and reviews by health authorities in multiple countries are continuing.

Note: This article summarizes findings from a multi-country media investigation and statements from clinicians and geneticists. Families affected by hereditary cancer syndromes should seek personalized advice from qualified medical professionals.