A sperm donor who unknowingly carried a rare cancer-causing genetic mutation has fathered nearly 200 children across Europe, with some children already dying from cancer and many others at high risk for developing the disease, according to a major investigation by European news organizations.
The Mutation and Its Impact
The donor carried a mutation in the TP53 gene, which is linked to Li-Fraumeni syndrome—a rare disorder that dramatically increases the risk of developing multiple cancers, including leukemia, brain tumors, and sarcomas. Children who inherit this mutation have up to a 90% chance of developing cancer by age 60.
How the Donor Was Identified
The donor was an anonymous man who began giving sperm for payment while he was a student in 2005. His samples were used in treatments for roughly 17 years. Up to 20% of his sperm carried the mutation, which could not have been detected with standard screening methods at the time of donation. The mutation likely arose in his testes and spread rapidly among his sperm cells, a phenomenon known as “selfish spermatogonial selection”.
Scope and Response
The sperm was used to conceive children in Denmark, Belgium, Spain, Greece, Germany, Ireland, Poland, Albania, Kosovo, and Sweden. At least 197 children have been identified, with 23 confirmed to have inherited the mutation and 10 already diagnosed with cancer. The Danish European Sperm Bank immediately blocked the donor once the mutation was discovered and acknowledged that the sperm had been overused.
Denmark’s European Sperm Bank has publicly acknowledged the scale of the case and addressed families directly. The company said it extends its “deepest sympathy” to all affected families and admitted that the donor’s sperm was used to create too many pregnancies in some countries, exceeding what it now views as appropriate limits.
Ethical and Regulatory Concerns
This case has sparked widespread concern about genetic screening standards and the limits on how many children a single donor can father. Experts are calling for stricter regulations and more advanced genetic testing in fertility clinics to prevent similar tragedies in the future.
