Hemoglobin D is a relatively rare disease first reported in 1951. We present the first reported case of Hemoglobin DC disease. This is a case of a Hemoglobinopathy with DC disease in a woman with a previous diagnosis of Hemoglobin SC disease. A 19-year-old woman presented to the Adult Hematology clinic at a tertiary care hospital in Northwest Louisiana for transition of care from Pediatric Hematology for a diagnosis of Hemoglobin SC disease diagnosed at the age 4. Historical data suggested no avascular necrosis, acute chest syndrome, and very few episodes of pain crisis. She has never taken hydroxyurea. Laboratory work showed persistently normal hemoglobin and white blood cell counts. All sickle cell preparations in the past were negative. Computerized tomography scan of the abdomen was reviewed and showed a spleen grossly normal in size and appearance. Given the incongruent clinical picture for sickle cell disease, repeat hemoglobinopathy evaluation with Capillary electrophoresis and confirmatory acid electrophoresis (to differentiate hemoglobins that co-migrate with Hemoglobin S) showed a probable double heterozygote for Hemoglobin D and C with suspected coexistent alpha thalassemia minor based on red blood cell indices. This case confirms the importance of the required confirmatory method to ensure a correct diagnosis since a misdiagnosis can lead to numerous adverse clinical or psychological effects for patients.©Copyright: the Author(s).