Reliable routine estimation of small amounts of foetal haemoglobin by alkali denaturation.

Several methods have been developed for the estimation of foetal haemoglobin levels by alkali denaturation (Singer, Chernoff, and Singer, 1951; Betke, Marti, and Schlicht, 1959; Kristoffersen, 1961) but there have been increasing demands for a simple method which is sensitive enough to measure reproducibly small elevations of foetal haemoglobin in both inherited and acquired haematological disorders. The method described by Betke et al (1959) comes closest to fulfilling these requirements. We describe a modification of this method which is simple and gives highly reproducible results in the lower range of haemoglobin F values.