More than half of all new stem cell donors registered in South Africa in 2025 were between the ages of 17 and 25. And, according to a growing body of medical research, they are also the most valuable donors on the planet.
Research analysing more than 10 000 stem cell transplants has found that for every ten-year increase in donor age, patient survival rates two years after transplant decline by approximately 6 to 7%. Donors aged 17 to 25 consistently provide patients with the best chance of survival. A separate long-term study found that transplants from younger donors successfully engrafted up to 30 000 stem cells that continued contributing to blood production for decades, compared to a tenfold decrease in transplants from older donors. It has also been confirmed that donor age has a greater influence on transplant success than previously assumed, with younger donors associated with improved overall survival and reduced relapse risk.
The evidence is bearing out in South Africa’s own numbers. DKMS Africa’s donor base has grown from 18 801 in 2021 to more than 173,000 by the end of 2025, a ninefold increase in four years. New sign-ups in 2025 alone reached more than 60,000, nearly double the 2023 figure. The 17 to 25 age group has led that charge, growing from 19% of new donors in 2021 to 56% in 2025. Forty percent of last year’s new donors were between 17 and 21.
Context matters: every hour, someone in South Africa is diagnosed with blood cancer. For many patients, a stem cell transplant from a matched, unrelated donor is the only viable path to survival. The match they need may already be on the registry. Or it may not exist yet.
“In South Africa, finding a compatible donor depends on human leukocyte antigen (HLA) characteristics that are inherited and vary significantly across ethnic groups. Patients have the highest probability of finding a match within a registry that reflects their own background. Currently, patients from black, coloured and Indian communities face considerably lower odds than those from communities better represented in local and international registries. A registry that grows without also diversifying fails the patients who need it most. That is why more young people of diverse backgrounds need to step forward and close this gap,” says Palesa Mokomele, Head of Community Engagement and Communications at DKMS Africa.
She adds, “This Youth Month, we need every young person who has not yet registered to know that their moment is now, and every adult who has not yet registered to ask themselves honestly: what is my excuse?”
The registration process takes minutes: a free swab kit arrives by post, is completed at home, and returned. No blood is drawn. No appointment is made. A registered donor is only contacted if they prove to be a genetic match for a patient in need, and even then, the decision to proceed remains entirely theirs. Registering is the first step. Following through, if called upon, is the one that saves a life.
To register, visit www.dkms-africa.org.
