Sickle Cell Trait

Acceptability at Recruitment

QUALIFIED

Acceptability at CT / Work-Up

QUALIFIED

Individual at Risk

Donor

Explanation of Condition

Sickle Cell Trait (SCT) is an inherited carrier state in which an individual carries one abnormal allele of the β-globin gene. This results in a heterozygous state consisting of sickle haemoglobin (HbS) and normal adult haemoglobin (HbA). It is present in over 300 million people worldwide. It is particularly frequent in individuals of African, Middle Eastern, Mediterranean, and Indian ancestry due to selection pressure for its protective effect against malaria. However, SCT may be present in individuals of any ethnic background.

Historically SCT donors were only permitted to donate via bone marrow harvest due to perceived risk of sickling within the apheresis circuit. However, a review of evidence by WMDA donor suitability committee has lead to change in guidance announced in October 2026. There is no evidence of clinically significant sickling or other sickle cell disease-associated with complications during or after mobilised PBSC collection or bone marrow harvest in donors with SCT.

Assessing donor suitability for either PBSC or bone marrow, attention should be paid to the donor’s additional risk factors for pulmonary embolism (especially a personal or close family history of venous thromboembolism), dehydration, pre-existing splenic disease, or chronic kidney disease. With individualised donor risk assessment if any of these risks are identified. As for all donors, they should be evaluated for co-morbidities, be adequately hydrated, and receive appropriate analgesia before and during, and after progenitor cell mobilisation by apheresis or bone marrow harvest.

For recipients of diverse ethnicities who may have a limited choice of donors, the consequences of donor-derived SCT are outweighed by the chance of cure.

Guidance

Please note this guidance applies to SCT only - Sickle cell disease (HbSS) and other variants (HbSC, HbSBthal, HbSD) are not acceptable.

At Recruitment

ACCEPTABLE

At CT / Work-Up

QUALIFIED

If otherwise suitable, the donor could be ACCEPTED for mobilised PBSC collection or bone marrow harvest.

Attention should be paid to the donor’s additional risk factors for pulmonary embolism (especially that of a personal or close family history of venous thromboembolism) or for chronic kidney disease.

Transplant centre should be informed about donor SCT prior to transplant

Guidance for CORD BLOOD DONATION

May donate if either parent has SCT, but cord unit should be tested for haemoglobinopathy before banking.

If the cord blood or infant/child is tested for the condition and is shown to have SCT, accept and inform the transplant centre.

Pseudonyms or Related Conditions

Sickle Cell Carrier

Other relevant pages

Haemoglobin Disorder

Version

Version 1, Edition 2

Date of Last Update

15th June 2012 29th October 2026