The Switch From Fetal (HbF) to Adult (HbA) Hemoglobin is Regulated by Various Transcription Factors and Cofactors. Regulators of this process constitute potential therapeutic targets for patients with the major hemoglobin disorders. Positive and negative interactions are denoted by pointed and blunt arrows, respectively. Dotted lines indicate the physical interactions between BCL11A and other cofactors. The dashed line indicates relationship with a lower level of experimental support.