Quantitation of fetal hemoglobin

Abstract

The quantitation of fetal hemoglobin (Hb F) is often necessary to establish the precise diagnosis of a hemoglobinopathy. The proportion of Hb F in normal adults is less than 1%. An elevated level of Hb F is found in approximately half the B-Thalassemia (Thal) heterozygotes, in oB-Thal and HPFH heterozygotes or homozygotes, and in many Hb S homozygotes and other conditions. The quantitation of the Y chain composition of Hb F and its distribution among red cells help to identify specific types of thalassemia such as the GYA y(OB)0-thal or GYA(yOB)0-thal or the different types of GyB+ HPFH and may contribute to an understanding of the hematological and clinical outcome of some of these diseases. Many procedures have been developed to evaluate the proportion of Hb F in a hemolysate, the Y chain composition of Hb F, and the intercellular distribution of Hb F. Some of these procedures are described in detail in other chapters, but most will be summarized here.