Hemoglobin F

(HbF; Syn fetal hemoglobin); a tetramer composed of two alpha (&#945;) chains and two gamma (&#947;) chains and the main oxygen transport protein in the fetus during the last seven months of development in the womb

Description
By the sixth month after birth, most of HbF has been replaced by adult hemoglobin (HbA) which is composed of two &#945; chains and two &#946; chains. Functionally, fetal hemoglobin differs most from adult hemoglobin in that it is able to bind oxygen with greater affinity than the adult form, giving the developing fetus better access to oxygen from the mother's bloodstream. Many drugs and substances have been found to induce HbF in adult life. Hemoglobin F inducers can be of therapeutic value in patients with deficient &#946; chain production (&#946;-thalassemia patients) or abnormal &#946; chains (sickle cell disease patients), provided they are of acceptable tolerability and toxicity.