For over 15 years, a Danish sperm donor fathered at least 197 children across Europe through the European Sperm Bank. DW's investigation reveals he carried a rare TP53 mutation that greatly increases childhood cancer risk.

Many families were informed years late — or not at all — raising concerns about clinic oversight. Experts are now calling for global donor limits and an international registry to prevent similar cases.

Story reported by: DR, RTBF, VRT, NOS, SVT, RUV, DW, NRK, RTVE, ORF, YLE, FTV and BBC, coordinated by the EBU Investigative Journalism Network. 

Do you or your child carry a genetic mutation or disease likely linked to an egg or sperm donation? Get in touch: investigations@dw.com 

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