A Belgian fertility clinic recently told a woman that the sperm donor she used in 2011 carried a rare TP53 gene mutation that greatly increases lifetime cancer risk and can be passed to children with a 50% probability. The mother was told it was urgent to test her teenage daughter; the daughter tested positive. The donor, identified in this investigation as donor 7069, was permanently blocked by the European Sperm Bank (ESB) in October 2023 after the mutation was confirmed in his stored samples.
An investigation coordinated by the EBU Investigative Journalism Network and executed by DW and several European public broadcasters found that, over more than 15 years, the ESB sold sperm from donor 7069 to fertility clinics in at least 14 countries. The bank exported his samples to 67 clinics and at least 197 children were conceived with his sperm; the true total may be higher because the ESB has not published a full count. Some donor-conceived children have already developed cancers and, according to biologist Edwige Kasper, some families report deaths among those affected.
Timeline and testing
The donor’s profile first appeared online as early as 2007 under the name “Kjeld.” In 2020 the ESB was notified that a child conceived with his sperm carried the TP53 mutation. The donor’s stored material was quarantined and retested; early results were reported as negative. The ESB says that later review showed the mutation was present only in a portion of the donor’s sperm cells (a condition called mosaicism), which can make it difficult to detect on some tests. Because the donor had no symptoms, his material was returned to the market.
In 2023 a second child was diagnosed with the mutation. More extensive testing then detected the mutation in part of the donor’s sperm, prompting the ESB to ban him permanently and attempt to notify clinics and families. The ESB says it contacted clinics and parents “as soon as possible,” but multiple families report receiving no official notification. In at least one case a computer migration at the bank temporarily lost contact details, delaying outreach by about 18 months.
Notification failures
Under European practice, sperm banks are expected to alert clinics about genetic abnormalities and clinics to notify recipient parents. The investigation found many families learned about the donor’s status only through other parents or media reports. Parents and clinicians described frustration and alarm that some affected children were not identified earlier and therefore missed the chance for early, life-saving surveillance.
Why the mutation matters
TP53 mutations require lifelong, regular medical monitoring because early detection of cancers associated with the mutation improves outcomes. These cancers can appear at young ages and be rare, so unless clinicians know a child carries the mutation, symptoms may be misattributed or missed.
Industry practices and regulation
The ESB, headquartered in Copenhagen and owned by private investment firm Perwyn, has expanded into a major exporter of donor sperm. In 2023 it reported profits of more than 60 million Danish kroner (about €8 million), up from 35 million the prior year. Sperm banks commonly publish donor profiles online and offer paid extras such as audio interviews, childhood photos and expanded genetic testing.
Routine donor screening does not typically include very rare mutations such as TP53. There is no international database linking donors across banks and countries, and economic incentives favor wide distribution of a single donor’s material: each frozen unit can sell for roughly €1,000 and a donor’s donations can be used many times. The ESB says it has self-imposed limits on distribution—most donors are capped at 75 families, with selected markets limited to 25 families and the option to buy exclusivity for a fee (the ESB cites €39,000). The bank acknowledged that limits were exceeded in some cases, blaming incomplete reporting from clinics, insufficient systems and fertility tourism.
Investigators found that the known number of children conceived with donor 7069 exceeded ESB policy and national rules in several places. Belgium recorded 53 children from the donor despite a national limit of six women per donor, prompting national investigations.
Regulation across Europe varies: some countries cap offspring numbers or restrict treatments, while others have few formal limits. Germany has no federal legal cap, though industry guidelines often suggest 15 families and some banks set their own limits. New EU regulations on assisted reproduction passed in 2024 do not establish an EU-wide cap on donor offspring.
Calls for change
Donor-conceived people and advocacy groups are calling for stricter family limits per donor and for registries to enable rapid notification if a donor is later found to carry a dangerous mutation. Spenderkinder, a German association of donor-conceived people, has proposed a global cap of six families per donor and a global registry. Clinicians and bank operators who spoke with investigators said improved tracking and tougher controls are needed to prevent similar public-health and ethical risks.
Human impact
Parents and clinicians describe profound emotional and practical consequences. A mother who learned only recently that her daughter carries the mutation said she feels enormous guilt that a fertility treatment choice may have transmitted a life-threatening genetic risk, even though the donor was unaware he carried it. Families now face a lifetime of surveillance, difficult medical decisions and uncertainty about long-term outcomes.
Reporting partners for this investigation included DR, RTBF, VRT, NOS, SVT, RUV, DW, NRK, RTVE, ORF, YLE, FTV and the BBC, coordinated by the EBU Investigative Journalism Network. Edited by Milan Gagnon; fact-checking by Julett Pineda and the EBU Investigative Journalism Network; legal support by Florian Wagenknecht.
If you or your child carry a genetic mutation or disease that may be linked to an egg or sperm donation, investigators ask you to contact [email protected].