What is the main cause of SCD?

Sickle Cell Disease (SCD) is primarily caused by a mutation in the HBB gene, which encodes the beta-globin subunit of hemoglobin. This mutation leads to the production of abnormal hemoglobin known as hemoglobin S (HbS). Under low oxygen conditions, HbS causes red blood cells to become rigid and sickle-shaped, resulting in various complications such as pain, anemia, and increased risk of infections. The condition is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene to develop the disease.