Frequently Asked Questions

Sickle cell disorder and thalassaemia are both inherited blood disorders where people are often treated with blood transfusions.

In sickle cell disorder, the red blood cells are often damaged and can then become stuck in blood vessels, causing pain and damaging organs. This can cause life-threatening complications such as stroke and severe breathing difficulties.

In thalassaemia, people cannot produce enough haemoglobin, causing severe anaemia, which can be fatal if not treated with blood transfusions.

Although anyone can have these conditions, sickle cell disorder is more common in people of Black African or Caribbean heritage and thalassaemia is more common in people of Mediterranean, South Asian, Southeast Asian or Middle Eastern heritage.

Sickle cell disorder affects about 17,000 patients in England with 250 new cases per year, and there are approximately 800 people with severe thalassemia, with about 50 new cases per year.

Rare inherited anaemias include Diamond-Blackfan anaemia (DBA), congenital dyserythropoietic anaemias (CDA), congenital sideroblastic anaemias (CSA), and disorders of red cell membrane and enzymes, such as hereditary spherocytosis and pyruvate kinase deficiency. These can be severe conditions and sometimes people need regular blood transfusions. 

We are only offering testing in these disorders if patients need regular blood transfusions – are ‘transfusion dependent’. There are about 200 patients in England who fit these criteria.

You should be offered this testing when you are having blood tests at the hospital once we have started the blood group genotyping programme – we think this will be in autumn 2023.

When testing begins, there will be patient information leaflets that you can read to find out more. Your clinical team will tell you about the test and ask for your consent to take the sample.

Red blood cells have labels on their surfaces, known as antigens or blood groups.  
 
We inherit our blood groups from our parents and different people have different blood groups.  

There are over 300 different blood groups, although the most important/well known ones are A, B and O, and RhD positive and RhD negative. We call these the basic blood groups.  
 
Blood is selected for transfusion - so the blood groups of the donor match those of the patient receiving the blood as closely as possible. This is known as blood matching. 

Before a person receives a transfusion, they have a test in the hospital to check their basic blood groups. When the blood laboratory team choose blood for patients, they check that the blood group of the donors matches the basic blood groups.

No. There are over 300 blood groups. Hospitals will match for the most important or well known blood groups. The most important ones are A, B, O and RhD positive and RhD negative. For people with sickle cell disorder, thalassaemia or some rare inherited anaemias, they will match for more blood groups, usually C, c, E, e and K.

However, we cannot routinely match for all of the 300 blood groups – known as the extended blood groups.  A major reason for this is to do with our current technology. 

As we don’t match for all the blood groups, transfused blood may contain blood groups that the patient does not have. Most of the time, the patients’ immune system ignores this, but sometimes the immune system recognises the difference and makes an antibody against the blood group. This is known as a blood group antibody formation or alloimmunisation. 

If you have developed an antibody, the laboratory needs to find blood that doesn’t contain that blood group for the next transfusion. This might be quite difficult to find if it is a minor blood group, leading either to a delay in transfusion or not enough blood being available for your transfusion. Either way, this could cause you to become more unwell.

We mostly do this using serology - by using commercially made antibodies to different blood groups in patients and donors. This is both time-consuming and expensive and we do not have the antibodies nor resources to test all the different blood groups of patients and donors.

As blood groups are determined by people’s genes, we can test for them with genetic testing. We do have some genetic testing available to patients (not donors) but this also does not test every blood group, is relatively slow, and not in routine use.

In 2014, a national audit undertaken by NHSBT showed that the extended blood groups were only known in 50% of patients with sickle cell disorder and thalassaemia. This makes it harder to identify antibodies if they form them and also harder to find better matched units for transfusion.

If more patients and donors are tested for extended blood groups using the new blood group genotyping assay, in the future it will be possible to ensure that transfused blood is more closely matched for the recipient, which will help stop antibodies forming.

It will also make it easier to find compatible blood for people who already have antibodies. This has already been shown to work in the Netherlands, where they have used this technology, to find matched blood for patients who previously could not have transfusions.

This technique also tests for different antigen types (called human leucocyte antigen - HLA), which may help people who need a bone marrow transplant find a matched donor.

While it’s not possible to predict for individual patients, we expect that as more of the patients and the donors have their blood group genotyped, it will be increasingly possible to provide better matched blood.

Alongside the genetic blood grouping, the sample will be tested for human leucocyte antigens (HLA) as people may be eligible for stem cell / bone marrow transplant / gene therapy treatment or clinical trials.

The first step would be to see if their sibling is a match. Siblings will be tested by the normal routes and the tests offered on patients as part of this programme are screening tests. If they show the possibility of matching more testing will need to take place.

Find more about the sickle cell disorder stem cell transplant programme.

There are BHS policies for  stem cell transplants in adults with sickle cell disease and thalassaemia

For several years we have been able to test blood groups using genetics or DNA – known as blood group genotyping.

NHSBT, working with an international group of scientists and industry, has developed a more advanced method of blood group genotyping

This newer DNA based blood group genotyping test can test for more blood groups than previous tests. The new test has the capability to test more patients and for the first time, blood donors can be tested routinely using genetic blood group testing.

Testing for bone marrow type (human leucocyte antigen - HLA) will also be offered as part of this programme.

Using donor and recipient blood group genotyping data to support matching for extended blood groups will, in the future, enable NHS Blood and Transplant to provide the best possible blood for patients, reducing the risk of preventable complications.

For patients without antibodies it should be possible to identify better matched blood for transfusion and so reduce antibody formation. For those that already have antibodies it should be easier and quicker to find blood for transfusion.

By also testing HLA types, people who are potentially eligible for stem cell/bone marrow transplant/gene therapy will have taken the first step to see if they have a related HLA matched donor.      

You should have had your full extended blood group tested. This is a national standard, though when we looked at this, it turned out that only half the people with sickle cell and thalassaemia had had this done. This full extended blood group has always been tested by the blood service, NHS Blood and Transplant (NHSBT).

Hospitals send NHSBT samples regularly for these and other tests. The way this is different is that this test covers many more of your blood groups than ever before and is faster and more efficient, so we hope to also offer it to all our donors in the future, enabling us to match blood more easily and also find donors for our patients who have very complex blood transfusion needs.

This test will use genetics (your DNA) to determine your blood groups – we call this blood group genotyping. We have used DNA before but this test is an improvement on previous ones.

Yes. The patient or donor only requires a simple blood test, and they do not come into contact with the new machine.

The programme will use array genotyping on the Axiom Total Blood Typing Solution Test on the GENE-TITAN platform, developed by the Blood transfusion Genomics Consortium. The Blood transfusion Genomics Consortium, of which NHSBT is a member, includes other blood services internationally Australia, Canada, the New York blood centre, South Africa, Finland and the Netherlands and industry partner, Thermofisher.

NHS England is funding NHS Blood and Transplant to provide the testing for patients in England free of charge to hospitals until a date to be confirmed. Following that, it should be expected that hospital trusts will be charged for the testing.

This blood group genotyping test can be offered to all current patients with sickle cell, thalassaemia and transfusion dependent rare inherited anaemias free of charge to hospitals in England through the NHS until March 2024 For patients not tested during this period, we expect to offer the blood group genotyping test to these patients and new patients (circa 300 new-borns and importations) in future years.

The testing in this first phase is being offered to people with sickle cell disorder, thalassaemia and transfusion dependent rare inherited anaemias for extended blood group testing and HLA testing only. Those with rare inherited anaemias will need to be transfusion-dependent to be eligible.

This is not for people who are carriers (trait) for sickle cell or thalassaemia. In the initial phase, whilst NHSE is paying for the testing, only patients in England with an NHS number will be eligible for this test. As Scotland, Wales and Northern Ireland set up their pathways and processes, testing will be offered to patients in those countries.

Staff and patients in these countries should await communication from their respective blood services prior to starting sample collection. 

No, this is not research. This is going to be offered as standard care, starting with the patients most affected by issues around blood matching – that is, people with sickle cell disorder, thalassaemia and those with transfusion dependent rare inherited anaemias.

Research may well be ongoing in your hospital as it is within the wider NHS. However, this blood group genotyping programme is not a research study, this is an improvement in clinical care, and it will be delivered by regular staff in clinics, wards and laboratories working with NHSBT.

Research is vital in providing the evidence we need to transform services and improve outcomes, and this is particularly important for people with sickle cell disorder thalassaemia and rare anaemias. A lot of health research is carried out in the NHS, with recruitment and follow-up often taking place in clinical settings.

You can find out more about research on the NHS England website.

The start date for patients with sickle cell, thalassaemia and transfusion dependent rare inherited anaemias, in England, and with an NHS number is 22 January 2024. For patients in Scotland, Wales and Northern Island, patients and staff should wait for communications from the respective blood services as to commencement of sampling.

The test also looks at another type of blood cell, namely platelets, and can be used to tell us a patient’s or donor’s platelet (HPA) type.

For this programme we will not be analysing this data and will not report any platelet results or add them to your patient record.

The genetic information about platelet types will be stored securely and will not be accessed unless we ask for and receive your permission (consent) in the future. No other genes will be tested beyond those.

This test will be been made available to those living in Northern Ireland, Scotland and Wales, through the health services of those countries. Systems are being put in place and sampling in those countries will start in due course. Staff and patients in those countries should await communication from their respective blood service before the start of sampling.

transfusion@nhsbt.nhs.uk

The testing will be done using DNA taken from a blood sample, similar to a blood sample for the group and screen test you may be familiar with. The sample will go to your local transfusion laboratory who will send it to NHSBT for testing.

This is the same as what happens at the moment for complex blood testing and investigation of transfusion reactions.

Yes, you should be. We’ll be encouraging your doctor to share the results of the blood group testing with you as appropriate.

It is essential that patient information is kept safe and secure. Your results will be treated in the same way as all samples sent to NHSBT; that is, blood samples tested by NHSBT are routinely available to the hospital that has sent your sample and can be viewed by other hospitals that you attend, so as to ensure the safety of any blood transfusion that you have.   

This programme complements a separate, existing programme in NHSBT to blood group genotype a number of blood donors. Using donor and patient genotyping data to support matching for extended blood groups will enable the NHS to provide the best possible blood for patients, reducing the risk of preventable complications.

NHSBT aims to genotype 80,000 carefully selected donors in 2024 with an ongoing ambition to genotype more donors in the future.

There is also a partnership with Our Future Health that will support donor genotyping. 

Testing will be performed in NHSBT laboratories, initially in Bristol.

Genetic testing of any sort requires consent. Clinical staff must obtain verbal consent and document this via a tick box on the sample form . The sample will not be processed without this box being ticked.

NHS Genomic Laboratory Hubs (GLHs) are not involved in this programme. All extended blood grouping in England, serological and genetic, is performed by NHSBT.

The NHS GLHs will continue to provide the specialist testing to make the diagnosis of these conditions for example for Sickle cell disorder, thalassaemia and rare inherited anaemias.

This method has been extensively validated on more than 13,000 samples by the International Blood Transfusion Genomics Consortium. The assay is pending approval for exceptional use authorisation by the MHRA. The assay is not currently CE marked.

We do not anticipate we will be using this new technology for emergency testing.

Emergency testing will continue to be performed using the standard genotyping array and a request must be made directly to NHSBT for this to be urgently undertaken if that is clinically indicated. This test will continue to incur a cost.

The testing is a simple blood test using DNA taken from the blood sample.

The sample will go to the local transfusion laboratory, who will send it to NHS Blood and Transplant for testing. The patient does not need to be fasting and can be taken at any time. We hope that eligible patients are offered this testing when they are having other blood tests e.g. when they come for an annual review or are admitted to hospital or seen in clinic.

The test will be explained and the patient asked for consent. The sample form will include a tick box on consent which must be completed - the sample will not be processed without this box being ticked.

A patient information leaflet alongside all other relevant information can be found on the genotyping programme homepage.

The test also looks at another type of blood cell, namely platelets, and can be used to tell us a patient’s or donor’s platelet (HPA) type.

For this programme we will not be analysing this data and will not report any platelet results or add them to the patient record.

The genetic information about platelet types will be stored securely and will not be accessed unless we ask and receive permission (consent) in the future.