Which statement describes HbSC disease?

Which statement describes HbSC disease?

• A. Inherit HbS and HbA
• B. Inherit HbS and HbD
• C. Inherit HbC and HbA
• D. Inherit HbS and HbC

Answer: (D)

HbSC disease happens when someone inherits one gene for sickle hemoglobin (HbS) from one parent and one gene for hemoglobin C (HbC) from the other. Both HbS and HbC are abnormal beta-globin variants, so having one of each creates a compound heterozygous state that produces a form of sickle cell disease. It’s different from inheriting HbS with normal HbA, which leads to sickle cell trait rather than disease, and from inheriting HbC with HbA, which is usually just a carrier state for HbC. There are other combinations like HbS with HbD that can cause other disease patterns, but HbS plus HbC specifically defines HbSC disease.

HbSC disease happens when someone inherits one gene for sickle hemoglobin (HbS) from one parent and one gene for hemoglobin C (HbC) from the other. Both HbS and HbC are abnormal beta-globin variants, so having one of each creates a compound heterozygous state that produces a form of sickle cell disease. It’s different from inheriting HbS with normal HbA, which leads to sickle cell trait rather than disease, and from inheriting HbC with HbA, which is usually just a carrier state for HbC. There are other combinations like HbS with HbD that can cause other disease patterns, but HbS plus HbC specifically defines HbSC disease.