A sperm donor carrying a rare cancer-causing genetic mutation has fathered nearly 200 children across Europe, according to an investigation led by the European Broadcasting Union, involving 14 public service broadcasters. The man, who appeared healthy and passed standard screening, donated sperm for approximately 17 years while he was a student.
The mutation, found in the TP53 gene, increases the risk of cells becoming cancerous. Children who inherit the mutation develop Li Fraumeni syndrome, a disorder associated with up to a 90 percent lifetime risk of cancer. Some donor-conceived children have already died, and many more are expected to develop cancer in the future.
Doctors first identified the risk this year after discovering 23 children carrying the mutation among 67 known cases, 10 of whom had already been diagnosed with cancer. Investigators reported that the donor’s sperm was used to conceive at least 197 children in 14 countries, though the actual number may be higher. Children have been born in Denmark, Belgium, Spain, Greece, and Germany, with additional recipients in Ireland, Poland, Albania, Kosovo, and Sweden. A small number of women from the United Kingdom were also treated at clinics in Denmark, according to Peter Thompson, chief executive of the UK’s Human Fertilisation and Embryology Authority.
Denmark’s European Sperm Bank, which supplied the samples, admitted the sperm was overused and expressed “deepest sympathy” to affected families. The bank said the mutation could not have been detected through routine screening and immediately blocked the donor once the problem was discovered.
Experts have described the case as both a regulatory failure and an extraordinary coincidence. Jackson Kirkman-Brown, a professor at the University of Birmingham, noted that detecting new mutations in sperm is difficult and that the core issue lies in insufficient monitoring of how often a single donor’s sperm is used. Clare Turnbull from the UK Institute of Cancer Research said the situation reflects a highly unusual combination: a donor carrying a rare mutation and that same sperm being used to create a large number of children. She added that the mutation likely arose in the donor’s testes and spread among sperm cells, a phenomenon known as selfish spermatogonial selection.
The investigation has also highlighted differences in European regulations on sperm donation. Family and child limits vary widely: in Cyprus, a donor may contribute to only one child, while France, Greece, Italy, and Poland allow up to 10. Denmark limits donations to 12 families, and Sweden and Norway to six families. Some countries maintain anonymous donations, though disclosure may occur in cases of severe health conditions.
Euronews Health has contacted the European Sperm Bank for comment but has not yet received a response. The case has renewed calls from experts for tighter international oversight of sperm donation to prevent similar incidents in the future.