Hereditary persistence of fetal hemoglobin. Heterogeneity of fetal hemoglobin in homozygotes and in conjunction with -thalassemia.

Abstract

The ratio of the Gγ to Aγ chains of human fetal hemoglobin was determined in 30 members of three Negro families. Family members with four types of condition were studied: those who were heterozygotes and those who were homozygotes for the hereditary persistence of fetal hemoglobin, those who had β-thalassemia trait, and those who had both β-thalassemia trait and the hereditary persistence of fetal hemoglobin. The results from heterozygotes with the hereditary persistence of fetal hemoglobin or with β-thalassemia agree with previous data from other subjects of these types. The results from homozygotes for the hereditary persistence of fetal hemoglobin suggest that an unknown factor alters the expression of the γ genes as compared to that of the ordinary heterozygotes. Increased synthesis of fetal hemoglobin in persons with a combination of the hereditary persistence of fetal hemoglobin and β-thalassemia may be directed by the β-thalassemia gene.