Microspectrophotometric Studies of Individual Erythrocytes from Thalassemia Patients. I. A Case of Double Heterozygosity for ^β-Thalassemia and Panglobinopenia?

Microspectrophotometric hemoglobin determinations on individual red cells from the peripheral circulation of a patient clinically characterized as a case of thalassemia major show the presence of two main cell populations, one normochromic and one hypochromic, with a ratio of total hemoglobin per cell of 2 to 1, a subnormal β-chain production in all cells, at mean levels that are in a ratio of 4 to 1 in the two cell populations, and a strongly stimulated γ-chain production in both cell populations with no bimodality of distribution. The mean cellular content of δ-chain is augmented. The ratios of 2 to 1 for total hemoglobin production is explained on the basis of the hypothesis that the case is one of heterozygosity for a β-thalassemia gene and a panglobinopenia gene with a mosaic condition realized at least in the case of the panglobinopenia gene. "Panglobinopenia" is described as a condition leading to a general inhibition of hemoglobin synthesis, perhaps through an inhibition of heme synthesis. To account for the observed cellular mosaic, it is proposed that panglobinopenia and perhaps thalassemia are examples of the well known phenomenon of variegation. This interpretation is now to be tested by applying the same methods to the study of further cases of thalassemia patients.