G gamma and A gamma globin chains separation and quantitation by isoelectric focusing

Isoelectric focusing in the presence of Nonidet P-40 splits human chromatographically pure γ globin chains into two bands of isoelectric points 6.95 and 6.85, respectively. The comparison of the relative proportions of the two bands with the ratios between the Gγ and Aγ non allelic chains of human fetal hemoglobin suggests that the band at pI 6.95 corresponds to Gγ and the band at pI 6.85 corresponds to the Aγ chain; the latter is the only band present in a patient with Greek type hereditary persistence of fetal hemoglobin, producing only Aγ chains. Fluorography of electrofocusing-separated radioactive γ globin chains synthesized by thalassemic reticulocytes indicates that the relative Gγ Aγ synthetic ratios are similar to the relative amounts of Gγ and Aγ chains accumulated in the erythrocytes, suggesting that the activities for the Gγ and Aγ mRNAs decay at roughly similar rates.