Mutations in stem cells of young donors can be passed to recipients

Stem cell donors may inadvertently be passing along disease-linked mutations to those who receive stem cell or bone marrow transplants to treat cancer and other blood disorders, according to a new study. It looked at data from 25 donors ages 20-58, and found that nearly 45% of the younger donors had mutations in transplanted stem cells that could increase recipients’ risk of certain conditions. Overall, nearly 85% of the mutations detected in all the donors were considered disease-causing and were missed by standard gene sequencing techniques. Although it was unclear if transplant recipients were actually experiencing related health issues, scientists say that the mutations are more likely to affect these patients — and not donors — because recipients’ immune systems are already weakened by disease and chemotherapy.