Almost 200 children were conceived with sperm from a donor with a cancer gene: “Several developed tumors and some have already died”

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

However, any child conceived from affected sperm will have the mutation in all cells of their body.

This is known as Li-Fraumeni syndrome and carries up to a 90% risk of developing cancer, particularly in childhood, and of developing breast cancer later in life.

“It’s a terrible diagnosis,” Professor Clare Turnbull, a cancer geneticist at the London Cancer Research Institute, told the BBC. “It is a very difficult diagnosis for a family to assimilate as having to live with this risk represents a lifelong burden, which is clearly devastating.”

MRIs of the body and brain and abdominal ultrasounds are required every year to detect tumors. Women often choose to have a mastectomy to reduce their risk of cancer.

The European Sperm Bank stated that “neither the donor nor his relatives suffer from any disease” and that this mutation “is not detected preventively through genetic testing.” They claimed they “immediately blocked” the donor as soon as the problem with his sperm was discovered.

Doctors caring for children with cancer related to sperm donation raised concerns with the European Society for Human Genetics this year.

They reported that they found 23 cases with the variant among the 67 children known at the time. Ten of them have already been diagnosed with cancer.

Through requests for information and interviews with doctors and patients, we can reveal that the donor has given birth to many more children.

The figure is at least 197 children, but may not be definitive as data is not available from all countries.

It is also not known how many of these children inherited the dangerous variant.

Dr. Edwige Kasper, a cancer geneticist at Rouen University Hospital in France, who presented the initial data, said:

“We have a lot of children who have already had one type of cancer, we have some children who have already had two different types of cancer and some of them have died at a very young age.”

Céline, not her real name, is a single mother living in France whose daughter was conceived 14 years ago with donor sperm and has the mutation.

She received a call from the fertility clinic she had visited in Belgium asking her to get her daughter tested.

He states that he bears “no grudge” against the donor, but says it was unacceptable that he was given sperm “that was not clean, that was not safe, that posed a risk.”

And they know that the cancer will haunt them for the rest of their lives.

“We don’t know when, we don’t know which one or how many,” he says.

“I understand that there is a good chance that it will happen, and if it happens, we will fight, and if there are several of them, we will fight several times.”

The donor sperm was used by 67 fertility clinics in 14 countries.

The sperm was not sold to British clinics.

However, as a result of this investigation, Danish authorities on Monday informed the UK’s Human Fertilization and Embryology Authority (HFEA) that several British women had traveled to the country to undergo fertility treatment using donor sperm.

These women have been informed.

Peter Thompson, chief executive of the HFEA, said that this was a “very small number” of women and that “the Danish clinic where they were treated informed them about the donor”.

We do not know whether British women were treated in other countries where donor sperm were distributed.

Concerned parents are advised to contact the clinic they attend and the fertility authority in their country.

The BBC has decided not to reveal the donor’s identification number as the donor made the donation in good faith and contacted known cases in the UK.

There is no law regulating the frequency of donor sperm use worldwide. However, each country sets its own limits.

The European Seed Bank acknowledged that these limits had “regrettably” been breached in some countries and that it was “in dialogue with the authorities in Denmark and Belgium”.

In Belgium, a single sperm donor can only be used by six families. Instead, 38 different women had 53 children with this donor.

In the UK the limit is 10 families per donor.

Professor Allan Pacey – who ran the Sheffield Sperm Bank and is now associate vice-president of the School of Biology, Medicine and Health at the University of Manchester – said countries had become dependent on large international sperm banks and that half of Britain’s sperm was now imported.

“We have to import from large international sperm banks who also sell it to other countries because that’s how they make money and that’s where the problem starts as there is no international law that regulates how often sperm can be used,” he told the BBC.

He said the case was “terrible for everyone involved” but that it was impossible to guarantee the complete safety of the sperm.

“You can’t check everything, in the current selection system we only accept 1% ​​or 2% of all men who apply to be sperm donors. So if we made it even stricter we would run out of sperm donors – that’s the balance.”

This case, as well as the case of a man who was ordered to stop sperm donation after giving birth to 550 children, raises again the question of whether stricter limits should be introduced.

The European Society for Human Reproduction and Embryology recently proposed a limit of 50 families per donor.

However, he cautioned that this would not reduce the risk of inheriting rare genetic diseases.

Instead, it would benefit the well-being of children who discover they have hundreds of half-siblings.

“More needs to be done to reduce the number of families born to the same donors worldwide,” said Sarah Norcross, director of Progressive Education Trustan independent charity for people affected by infertility and genetic diseases.

“We don’t fully understand the social and psychological impact of having hundreds of half-siblings. It can be potentially traumatic,” he told BBC News.

The European Sperm Bank said: “Particularly in view of this case, it is important to remember that thousands of women and couples have no opportunity to have a child without the help of donor sperm.”

“In general, it is safer to have a child using donor sperm if donors are screened according to medical guidelines.”

According to Sarah Norcross, these cases are “extremely rare” considering the number of children born from a sperm donor.

All the experts we spoke to said that going to an accredited clinic ensures your sperm is tested for more diseases than most expectant parents.

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