Homozygous Delta-Thalassemia First Discovered in Japanese Family With Hereditary Persistence of Fetal Hemoglobin

Abstract

A family with δ-thalassemia has been discovered, in which five members are thought to be δ-thalassemia homozygotes with complete deficiency of Hb A2, and three members are probably heterozygotes with low levels of Hb A2 (1.2-1.6%). In four members among these, persistence of fetal hemoglobin of Swiss type was observed. The formal genetics of these two entities was discussed. The proposita showed first thalassemia-like stigmata with iron deficiency anemia, but after iron therapy administered over 2 months, the stigmata disappeared. All the other members of the family were free from clinical symptoms with normal morphology, MCH, and osmotic fragility of the red cells.

Interaction between Homozygous β0 Thalassaemia and the Swiss Type of Hereditary Persistence of Fetal Haemoglobin

“…To obtain more information on this issue, we have carried out a preliminary analysis of the linkage utilizing all the families segregating for Hb S, p thalassaemia and the heterocellular type of HPFH published so far and reported by Wood et a1 (1976). To these pedigrees we have added the family of 111-2 and also the family reported by Ohta et at (1971) in which HPFH and 6 thalassaemia (or a 6 variant migrating with Hb A) are present. W e include this pedigree because of the close linkage between 6 and p loci.…”

The frequency in Japanese of genetic variants of 22 proteins

“…We interpret the proposita as resulting from homozygosity for the S-thalassaemia trait, as described by Ohta et al (1971). Our proposita has slightly more Hgb F than the average of the five cases described by the Japanese group (3.7%).…”