A case has been reported in Spain that could impact the entire system of donor and reproductive medicine. For the first time in the world, doctors discovered that a rare hereditary disease—angioedema—was transmitted to several children through an anonymous sperm donor. This development has sparked debate among experts and raised questions about the current safety protocols in fertility clinics.
The situation came to light after a child from a family who had used a fertility clinic began experiencing recurring facial swelling that did not respond to standard treatments. Genetic testing revealed the girl carried the T328K mutation in the F12 gene, which is linked to angioedema. Later, the same mutation was found in two other children who were also conceived using donor material from the same sperm bank.
Medical investigation
Doctors from Hospital Vall d’Hebron (Barcelona) and Hospital Universitario de Santa Maria de Lleida conducted a joint investigation. They found that none of the mothers carried this mutation, confirming the donor as the source. After contacting the clinic and reviewing the sperm bank, it was established that the donor did in fact carry this genetic trait, even though he showed no symptoms of the disease himself.
The clinic notified all women who had previously used this donor’s services. As a result, more carriers of the mutation were identified, some of whom showed no symptoms. This allowed experts to assess the potential risks and begin revising donor screening standards.
A rare disease and its features
Angioedema is an extremely rare genetic disorder characterized by sudden swelling of the skin, mucous membranes, and in some cases, the airways. Symptoms are especially common in women: experts estimate that up to 80% of female carriers experience the disease, while the risk is significantly lower for men. The condition is treatable, and with timely therapy, patients can lead normal lives. However, without medical intervention, attacks may last up to three days and pose a serious risk.
According to RUSSPAIN, recent years have seen an increase in cases of rare inherited diseases in Spain, detected after IVF procedures. This trend is linked to the growing number of donor programs and advances in genetic diagnostics. The case identified in Barcelona became the first officially confirmed instance of angioedema being transmitted via donor sperm, underscoring the need for stricter genetic screening of donors.
Implications for medicine
Experts note that this case could prompt a review of reproductive clinic regulations nationwide. Discussions are already underway about introducing expanded genetic testing for donors to minimize the risk of transmitting rare diseases. Doctors emphasize that even asymptomatic carriers may pose serious risks for future generations.
In Spain, thousands of families turn to donor programs every year. New data highlight the need to inform patients about potential risks and underscore the importance of timely detection of genetic mutations. According to russpain.com, such cases may not be isolated, but were previously unnoticed due to inadequate diagnostics.
Context and similar cases
In recent years, sporadic cases of hereditary diseases being transmitted through donor materials have been recorded in Europe and the US, but until now there have been no officially confirmed cases in Spain. In 2024, France discussed an incident involving the transmission of a genetic mutation via a donor egg, prompting legislative changes. In the UK, mandatory expanded screening was introduced for all donors in 2025 following a similar incident. These events demonstrate that the issue requires an international approach and ongoing improvement of safety standards in reproductive medicine.
