Sperm Donor Carries Cancer Mutation, Resulting in Nearly 200 Children

Wed Dec 10 2025 09:00:46 GMT+0200 (Eastern European Standard Time)

An investigation reveals a sperm donor with a genetic mutation that significantly increases cancer risk has unknowingly fathered at least 197 children across Europe, raising serious ethical and health concerns.

A recent investigation uncovers that a sperm donor with a mutation in the TP53 gene has fathered almost 200 children, leading to heightened cancer risks for these offspring. The European Sperm Bank has faced criticism for excessive usage of this donor's sperm, and affected families are grappling with the implications of potential hereditary cancer. Concerns have been raised about the screening processes for sperm donors, underscoring the need for better regulations in fertility treatments.

A sperm donor who unknowingly harbored a genetic mutation that dramatically raises the risk of cancer has fathered at least 197 children across Europe, a major investigation has revealed.

Some children have already died and only a minority who inherit the mutation will escape cancer in their lifetimes.

The sperm was not sold to UK clinics, but the BBC can confirm a very small number of British families, who have been informed, used the donor's sperm while having fertility treatment in Denmark.

Denmark's European Sperm Bank, which sold the sperm, said families affected had their deepest sympathy and admitted the sperm was used to make too many babies in some countries.

The sperm came from an anonymous man who was paid to donate as a student, starting in 2005. His sperm was then used by women for around 17 years.

He is healthy and passed the donor screening checks. However, the DNA in some of his cells mutated before he was born.

It damaged the TP53 gene – which has the crucial role of preventing the body's cells turning cancerous.

Most of the donor's body does not contain the dangerous form of TP53, but up to 20% of his sperm do.

However, any children made from affected sperm will have the mutation in every cell of their body. This is known as Li Fraumeni syndrome and comes with an up to 90% chance of developing cancer, particularly during childhood as well as breast cancer later in life.

Doctors who were seeing children with cancer linked to sperm donation raised concerns at the European Society of Human Genetics this year. Through Freedom of Information requests and interviews with doctors and patients, it was revealed that the figure is at least 197 children, but that may not be the final number as data has not been obtained from all countries.

The donor's sperm was used by 67 fertility clinics in 14 countries, leading to serious ethical questions about its distribution and the regulatory frameworks governing sperm donation.

As public scrutiny grows, there are calls for stricter regulations on sperm donor usage to prevent such occurrences in the future.