Almost 200 children conceived from sperm donor with cancer-causing gene

Sixty-seven fertility clinics used the donor's sperm in 14 different countries.

Sperm from a donor who unknowingly carried a cancer gene has been used to conceive almost 200 babies in Europe, according to an investigation by the BBC and 14 other publicly owned news organizations, along with members of the European Broadcasting Union’s Investigative Journalism Network.

Some children fathered by the donor have already died, and only a minority who inherit the gene will not have cancer in their lifetime, the British outlet reported.

The sperm was not used in the U.K., but a small number of British families who underwent fertility treatment in Denmark used the donor.

Denmark’s European Sperm Bank sold the sperm and said families affected had its “deepest sympathy,” adding that the sperm was used to conceive too many babies in some countries.

The sperm belonged to an anonymous man who was paid to donate in 2005, when he was 17 and a student. His sperm was used for about 17 years.

The man is healthy, and was healthy at the time of donation — he passed the necessary screening checks to donate, but some of his cells’ DNA mutated before he was born, damaging the TP53 gene, which plays a crucial role in preventing cancerous cells from spreading.

While most of the donor’s body does not contain the damaged gene, up to 20 per cent of his sperm do, the investigation found.

Any baby conceived from the affected sperm will carry the mutation in every cell in their body, leaving them with a genetic disorder known as Li-Fraumeni syndrome, which significantly increases a person’s chance of developing cancer in their lifetime, including brain tumours and childhood cancers such as leukemia.