Sperm donor passes cancercausing gene to 10 children.

A sperm donor who was used to conceive at least 67 children across Europe has been found to have passed on a rare cancer-causing mutation, with 10 of the children developing the disease.

- HOLLY EVANS

Twenty-three of the children, conceived between 2008 and 2015 across eight countries, have now been found to carry the variant, while some have been diagnosed with cancers such as leukaemia and non-Hodgkin lymphoma.

The case has raised concerns about the lack of internationally agreed limits on the use of a single sperm donor, and the difficulty in tracing a large number of families to inform them of a serious medical issue.

The news was uncovered after two separate families contacted their fertility clinics because their children had developed cancers that were linked to a genetic variant called TP53.