Sickle cell disease (SCD) is an inherited condition, so it’s present at birth. It occurs when a baby receives a copy of a specific mutated form of the HBB gene from both parents, which results in one or both beta globins (the beta chains of the hemoglobin molecules) being replaced by hemoglobin S. This type of gene inheritance pattern is called autosomal recessive, which means that disease happens only when both copies of the sickle cell gene are altered. This is possible only when both parents carry the mutation.[1] People born with only one copy of the altered gene don’t usually manifest any symptoms and live a healthy life, although they can still pass the defective gene to their children. This is called sickle cell trait (SCT).[reference|url=https://www.hematology.org/education/patients/anemia/sickle-cell-disease|title=Sickle Cell Disease: American Society
What causes sickle cell disease?
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•Last Updated: May 16, 2025
Sickle cell disease is an inherited condition caused by inheriting a mutated form of the HBB gene from both parents, which leads to the production of hemoglobin S. This autosomal recessive inheritance means that symptoms occur only when both copies of the gene are altered, whereas people with one altered gene typically do not show symptoms and are referred to as having sickle cell trait.