Regular blood donation is associated with distinct genetic changes in blood stem cells that may lower the risk of pre-cancerous mutations leading to blood cancers like leukemia, according to a Francis Crick Institute study published in Blood.
Study Overview
Researchers examined blood from 429 healthy men in their 60s 217 frequent donors (three times yearly for 40 years) versus 212 irregular donors (about five lifetime donations). Both groups showed similar natural mutation levels from aging (around 15-20 per stem cell), but frequent donors had a higher prevalence (50% vs. 30%) of beneficial DNMT3A gene mutations. These promote red blood cell production in response to erythropoietin (EPO) stress post-donation, unlike inflammation-driven pre-leukemic mutations.
Mechanism and Lab Insights
Donation stimulates bone marrow stem cells to regenerate, potentially selecting for clones that excel in healthy erythropoiesis. Mouse models confirmed these mutated human stem cells produced more red blood cells without cancerous proliferation, thriving in EPO-rich conditions mimicking repeated donations. Aging accumulates mutations, but low-stress renewal from donating may favor adaptive diversity over harmful ones.
Caveats and Future Work
The "healthy donor effect" fitter people donate more could bias results, as noted by senior author Dr. Dominique Bonnet and NHS Blood and Transplant's Dr. Lise Estcourt. No causation proven; larger studies including women are planned. Still, it reinforces donation's safety amid critically low UK stocks, with eligibility for fit 17-65-year-olds (excluding cancer history, HIV, recent tattoos, etc.
