28.05.2025.
A troubling case presented at the annual European Society of Human Genetics conference in Milan has revealed a serious regulatory gap across Europe when it comes to sperm donation — one that may have already led to multiple children being born with a high genetic risk of cancer.
French clinician and cancer genetics expert Dr Edwige Kasper of Rouen University Hospital shared the story of a donor who, though in good health, carried a pathogenic variant in the TP53 gene — a mutation now linked to Li-Fraumeni syndrome, one of the most severe hereditary cancer syndromes.
“I analysed the variant using population and patient databases, computer prediction tools, and the results of functional trials, and came to the conclusion that the variant was probably cancer-causing and that children born from this donor should receive genetic counselling,”
says Dr Kasper.
The mutation was identified after a patient received a letter from a private European sperm bank. The donor’s biological children were already showing signs of illness — leukaemia and non-Hodgkin’s lymphoma — prompting the definitive block of his remaining gametes.
An investigation across eight countries found 67 children from 46 families, with 23 carrying the mutation and 10 diagnosed with cancer so far. All were born between 2008 and 2015.
“This is heavy and stressful for carriers, but we have seen its effectiveness in that it has enabled early detection of tumours and thus improved patients’ chances of survival,” says Dr Kasper, referring to the intensive monitoring protocols now in place for affected children.
Despite advances in genetic screening, regulations vary widely across Europe. France limits sperm donors to ten births, but other countries allow up to 15 (Germany and Denmark) or even use the same donor for multiple families(UK: 10–12 families).
“There is a major issue here concerning a lack of harmonised regulation across Europe,”
says Dr Kasper.
“Some fertility clinics have refused to provide information to the families concerning the variant because they wanted the children to be tested in their own laboratories.”
In France, where donation is anonymous, voluntary, and free, the process is more tightly supervised. All genetic suspicions must be reported, and gamete use is strictly limited and authorised through Agence de la Biomédecine.
“The fact that the case in point is very rare does not mean that it will not reoccur,” says Dr Kasper.
“We need proper regulation at the European level to try to prevent it from happening again, and to implement measures to ensure a worldwide limit on the number of offspring conceived from the same donor.”
Prof. Alexandre Reymond, chair of the conference, backed the call for international oversight:
“While current legislation on assisted reproduction usually does not cross borders, this is a good example of why wider oversight is needed. But for now, what we learn in genetics in one country can help future parents everywhere.”
This alarming case underscores the urgent need for unified European regulation to protect future families from preventable genetic risks in assisted reproduction.
