Sickle Cell-Hemoglobin D Disease

**Semantic type:** Disease or Syndrome

**Definition:** A variant of sickle cell disease due to heterozygosity for hemoglobin S and hemoglobin D mutations. Patients present with the symptoms of sickle cell disease but the symptoms are less frequent and severe compared to patients with hemoglobin SS disease.

**Synonyms:** - Hemoglobin SD Disease