Sperm donor with cancer-causing gene fathered nearly 200 children across Europe

A sperm donor carrying a cancer-linked TP53 mutation fathered at least 197 children across Europe, a cross-border investigation has found.

Some children have already died and, for those who inherit the mutation, only a minority will escape cancer in their lifetimes, the investigation by 14 public service broadcasters found.

The sperm was not sold to UK clinics, but a “very small” number of British families used the donor’s sperm while having fertility treatment in Denmark.

Prof Clare Turnbull, a cancer geneticist at the Institute of Cancer Research in London, said: “It is a dreadful diagnosis. It’s a very challenging diagnosis to land on a family, there is a lifelong burden of living with that risk, it’s clearly devastating.”

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

The anonymous donor was paid to donate as a student starting in 2005. His sperm was then used by women for about 17 years. He is healthy and passed donor screening checks.

A mutation arose in some of his cells before birth, damaging TP53, a tumour-suppressor gene that helps stop cells becoming cancerous.

Up to 20 per cent of his sperm carry the altered TP53.

Children conceived from affected sperm have the mutation in every cell, known as Li Fraumeni syndrome, which brings up to a 90 per cent lifetime cancer risk.

Dr Edwige Kasper, a cancer geneticist at Rouen University Hospital in France, said: “We have many children that have already developed a cancer.

“We have some children that have developed already two different cancers and some of them have already died at a very early age.”

Peter Thompson, chief executive of the HFEA, said affected British women “have been told about the donor by the Danish clinic at which they were treated.”