Every blood donation saves lives. Yet for people living with sickle cell disorder, access to closely matched blood remains a growing and urgent challenge.
As we mark World Blood Donor Day on 14 June, it is an opportunity to highlight why donor diversity matters. There is a clear need, both in the UK and globally, for more blood donors from Black African, Black Caribbean and mixed heritage backgrounds. Addressing this gap is essential to improving care and outcomes for people living with sickle cell disorder.
Sickle cell disorder and the role of blood transfusions
Sickle cell disorder is an inherited blood condition that affects the shape and function of red blood cells. Instead of being flexible and round, the cells can become rigid and curved (“sickle”-shaped), making it harder for blood to flow smoothly through the body. This can reduce the amount of oxygen reaching tissues and organs and lead to serious health complications. The condition predominantly affects people from Black African and Black Caribbean backgrounds due to inherited blood traits.
People with sickle cell disorder can experience what is known as a sickle cell crisis, where misshapen blood cells block blood vessels and cause sudden, severe pain. Crises can also increase the risk of infection, organ damage and the need for urgent medical care.
For many, blood transfusions are a vital part of treatment. In some cases, transfusions are used occasionally, while for others they are required regularly (up to every few weeks) over a lifetime.
Transfusions can:
- Relieve pain
- Treat anaemia
- Prevent strokes
- Reduce the risk of complications
- and, in some cases, be lifesaving
Why matching blood and donor diversity matter
Given the frequency with which many people with sickle cell disorder require transfusions, ensuring compatibility is a critical part of their care. This helps to reduce the risk of immune reactions and other complications that can develop over time.
Matching goes beyond familiar blood groups such as A, B, AB and O, and includes more detailed blood subtypes. These variations are not evenly distributed across populations, meaning people are more likely to receive a close, compatible match from donors with similar ancestral backgrounds. This is why donor diversity is essential to delivering safer and more reliable care.
The blood subtype known as Ro, plays a critical role in sickle cell care:
- Ro is over 10 times more common in people from Black African, Black Caribbean and mixed heritage backgrounds.1
- In the UK in 2024, 56% of donors from Black heritage backgrounds had the Ro subtype, compared with 2.4% of donors from other ethnicities.2
Having Ro blood does not mean someone has sickle cell disorder. However, people with the condition are more likely to have Ro blood and therefore benefit from receiving closely matched Ro blood for safe and effective transfusions
A growing gap and a shared responsibility
Despite its importance, Ro blood remains in critically short supply. While it is relatively common within Black communities, only around 3% of regular blood donors in the UK have the Ro subtype.1 At the same time, advances in treatment mean that people with sickle cell disorder are living longer. This is a positive development, but it also increases the need for regular transfusions over a longer period of time.
Demand for rare blood subtypes such as Ro is rising by an estimated 10 – 15% each year1, creating sustained pressure on an already limited supply. This imbalance reflects a broader challenge in ensuring that donor pools adequately reflect the populations most likely to need closely matched blood. Addressing this will require both increased participation from underrepresented donor groups and greater awareness of how blood matching needs differ across communities.
How you can help
Ensuring access to well-matched blood relies on having a donor base that reflects the diversity of the communities it serves.
Whether by donating blood, sharing information, or encouraging others to get involved, individual actions can help strengthen the availability of closely matched blood for those who need it.
Representation in blood donation saves lives.
Find out more or register to donate (UK-based resources. We encourage you to seek local options in your country):
References:
[1] https://www.blood.co.uk/why-give-blood/demand-for-different-blood-types/the-ro-subtype-explained/
