treated with has causal genotype has causal or contributing genetic variation has manifestation has causal molecular phenotype in guideline Increased Hemoglobin F Hereditary Persistence of Fetal Hemoglobin This is a benign condition. Hereditary Persistence of Foetal Haemoglobin Sufficient SCDO:0000560 HPFH The persistence of substantial fetal hemoglobin production into adulthood, usually associated with hemoglobinopathies due to mutations in the alpha and/or beta chain of hemoglobin. NCIT:C129072 Osteonecrosis of the Femoral Head Hydroxyurea HBG1 and/or HBG2 Mutations Quantitative Hemoglobinopathy HBB, 106-KB DEL National Guideline for the Control and Management of Sickle Cell Disease Hereditary Persistence of Fetal Hemoglobin Genotype