Sperm Donor Mutation Linked to Cancers in 197 Children

A sperm donor carrying an undetected genetic mutation linked to a high risk of cancer fathered at least 197 children across 14 European countries, leading to multiple childhood cancer diagnoses and at least some early deaths among the offspring, according to an investigation by public broadcasters including the BBC.

The anonymous donor, a student at the time, began contributing sperm to Denmark's European Sperm Bank in 2005. His samples passed standard health screenings and were distributed to 67 fertility clinics over the next 17 years. The man remained healthy, but he possessed a rare mutation in the TP53 gene, which normally helps repair DNA damage and prevent uncontrolled cell growth. This alteration affects up to 20 percent of his sperm cells, though not the rest of his body. Children conceived from those affected samples inherit the mutation in every cell, resulting in Li-Fraumeni syndrome, a condition that carries a 90 percent lifetime risk of developing cancers such as brain tumors, leukemia, breast cancer, and sarcomas.

The issue surfaced in 2020 when doctors diagnosed a child conceived from the donor's sperm with the mutation. The bank quarantined the samples after...