modifies Phenotype of Sickle Cell Disease Altered Level of Normal Hemoglobin in SCD SCDO (Jade Hotchkiss) An altered level of normal hemoglobin (Hemoglobin A (Hb A), Hemoglobin A2 (Hb A2) or Hemoglobin F (Hb F, fetal hemoglobin) in the blood, which may be seen in those suffering with Sickle Cell Disease (SCD). None Probably too specific to SCD be included in other ontologies. Abnormal Hemoglobin Level in SCD