Ro blood

What is the Ro subtype and why is it important?

Please keep donating if you have the Ro subtype.

A donor holds an Ro blood bag tagWhat is the Ro subtype?

The Ro subtype is a variation of the Rh positive blood type. You might have it if you have O positive, A positive, B positive or AB positive blood.

Everyone has a blood subtype so having the Ro subtype does not mean there’s a problem with your blood.

Dr Alexander Weiner discovered these subtypes in 1943 and gave them simplified names, which is where the name ‘Ro’ comes from.

Why is the Ro subtype important?

Subtypes are important if you receive regular transfusions and need blood that’s compatible with both your blood type and your subtype.

The Ro subtype is particularly important for two reasons:

  • demand is increasing by 10-15% each year
  • only 2% of regular donors have the Ro subtype

So there’s a gap between the number of donations we collect, and the amount of Ro blood hospitals need.

Ro blood is a rare blood type and there are patients in real need of it.

We need more blood donors with the Ro subtype to make sure the right blood is available to everyone who needs it.

Finding out if you have the Ro subtype

You usually won’t find out blood type or subtype until you give blood for the first time.

If you have the Ro subtype, we'll let you know after your first donation. 

Did you know?

You are ten times more likely to have the Ro subtype if you are of Black African or Black Caribbean or Mixed heritage.

That’s one of the reasons why we need more Black people to become blood donors

Why is demand for the Ro subtype increasing?

Ro blood is vital in treating sickle cell – a group of inherited blood conditions that affect red blood cells.

245 babies a year are born with sickle cell.

The condition is often treated with regular blood transfusions so subtypes, such as Ro, are important in ensuring patients get blood which is most compatible with their blood type and subtype. 

Many people with sickle cell have the Ro subtype. This is because sickle cell more commonly affects people from Black ethnic backgrounds where the Ro subtype is more common.

There has been an increase in the number of people with sickle cell and as a result, the demand for Ro blood has grown.

Each year, a regularly transfused patient with sickle cell will need an average of 100 blood donors to stay alive.

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