Variations in globin chain synthesis in hereditary persistence of fetal haemoglobin.

Globin synthesis was studied in four Negro families including 10 members with Hb A-HPFH and four with Hb S-HPFH. The beta/alpha specific activity ratios in 10 of these HPFH heterozygotes were similar to those of the control group. In two patients with Hb A-HPFH, the beta/alpha ratio was slightly decreased in one (0.84) and clearly decreased in another (0.78). In two of the patients with Hb S-HPFH the ratios were clearly decreased (0.71 and 0.75). The extended range of beta/alpha ratios in these 14 patients is similar to that of Negro patients with beta-thalassaemia trait. These studies indicate that a decreased beta/alpha ratio may be found in HPFH, as well as in beta-thalassaemia. Bone marrow globin synthesis was measured in two patients with Hb S-HPFH and decreased peripheral blood beta/alpha ratios, and in one with Hb A-HPFH and a normal peripheral blood beta/alpha ratio. In each patient the (beta+gamma)/alpha ratio of radioactivities as well as the beta/alpha specific activity ratio was close to 1 and therefore balanced, indicating more rapid decay of beta-chain synthesis relative to alpha-chain during red cell maturation or extremely rapid destruction of newly synthesized excess alpha-chains in the bone marrow.