A Danish donor whose sperm cells contained a cancer-causing gene mutation fathered at least 197 children across 14 countries in Europe, a major investigation has found.
Many of the children developed cancer, with some dying at a very early age.
The donor's sperm was sold to Ireland, though no children were born from it.
Sperm from Donor 7069, alias 'Kjeld', was made available by the European Sperm Bank (ESB) to 67 clinics between 2006 and 2023, when it was blocked from the market.
The case represents an infringement of legal limits in place in a number of countries on the number of births per donor, the investigation from the European Broadcasting Union's Investigative Journalism Network revealed.
'Kjeld' was a student in 2005 when he started donating at the Copenhagen branch of the ESB after passing all medical tests.
In 2023, however, a gene mutation which dramatically increases the risk of cancer was discovered in a portion of his sperm cells, after doctors reported seeing children he fathered with the TP53 mutation.
It led to the issuing of an international alert to health authorities and fertility clinics.
The TP53 genetic mutation could not be detected in the initial medical tests in 2005 as it was present in a very small percentage of his sperm cells, the investigation revealed.
Sperm from the donor has been blocked since the discovery.
With doctors attempting to offer early screening and potentially life-saving advice, many of the affected children still have not been contacted.
The DNA alteration is known as Li Fraumeni Syndrome, an inherited genetic disorder, which can also be passed on by these children to their own future children.
Edewige Kasper, an oncogenetics biologist at Rouen University in France which is leading scientific research on the case, said the alteration is "a very, very severe and rare hereditary predisposition to cancer" which is "characterised by a wide tumour spectrum".
"We have many children that have already developed cancer, we have some children that have developed two different cancers and some of them have already died at a very early age."
The ESB said it immediately blocked the donor after the mutation was detected and notified authorities and clinics.
The clinics are responsible for notifying affected patients, it said.
However, some parents instead learned the news from a network of families with children from the same donor before being contacted by clinics.
Limits exceeded on children born to donor
The donor’s sperm was sold to Ireland, Danish health authorities confirmed, though no children were born from it.
There is no law in Ireland limiting the number of children that can be born to a single sperm donor.
The ESB states on its website that the majority of its donors have a limit of 75 families.
Fertility clinics in Ireland have listed the family limit for ESB donors as four families.
Figures show the donor’s sperm was used to conceive 49 children in at least 33 Danish families and 50 children with non-resident women treated at Danish clinics.
A non-binding recommendation from national authorities capped at 25 the number of families using sperm from one donor in Denmark at the time.
In Belgium, Donor 7069’s sperm resulted in the births of 53 children and exceeded the country’s legal limit of six families per donor.
A subsequent inquiry in Belgium into the fertility industry found that a further 28 Danish donors were blocked between 2022 and 2025, due to risk of hereditary disease.
Chief physician for Supervision and Guidance at the Danish Patient Safety Authority Bente Møller said that compliance with donor children limits "is a trust-based system" where "the sperm bank has the duty to comply with the quotas specified both in Denmark and abroad.
"We were surprised that the scale is as large as it is here, and it is completely unacceptable. We do not track the specific numbers, but we monitor that the sperm banks have systems in place that allow them to keep track of it," she said.
The global fertility services market is valued at over €45 billion, according to research by Grand Market Research.
With declining fertility rates and changes in family structures, Europe is one of the industry's largest markets.
Legal experts argue that current EU legislation does not adequately address critical ethical and medical issues that have arisen as patients seek treatment across borders.
Accreditation: EBU Investigative Journalism Network
