In Europe, 200 children were conceived from a sperm donor with a gene mutation leading to cancer.

A sperm donor with a gene mutation that radically increases the risk of cancer has fathered 200 children across Europe. This was revealed during a large-scale investigation conducted by major broadcasters, including CBS News and BBC News.

Some children conceived using donor sperm have already died from cancer, and the vast majority of those who inherit the gene will develop the disease during their lifetime, geneticists say.

The CBS News website writes that the man was tested before becoming a donor at the European Sperm Bank while still a student in 2005. His sperm was used by women from various countries for 17 years.

According to the results of the investigation, the cancer-causing mutation occurred in the TP53 gene, which is responsible for suppressing the development of malignant tumors. The mutation causes Li-Fraumeni syndrome, in which the risk of developing cancer, especially in childhood, is 90%.

In 2023, two families contacted reproductive medicine clinics whose children were diagnosed with cancer, presumably related to Li-Fraumeni syndrome. After this, the donor’s sperm was no longer used for conceptions.

The donor himself does not have Li-Fraumeni syndrome, but about 20% of his sperm contain the mutated gene.