Identification of Abnormal Hemoglobin IX． HbA2 Yokoshima δ25（B7）Gly→Asp Found in Homozygous State in Two Japanese Families

A variant of HbA2 was found in two patients during a random survey by isoelectric focusing. Chemical characterization of the zbnormal δ chain was facilitated by reverse phase high performance liquid chromatography and automated gas phase amino acid sequencing. The same amino acid aubstitution, from glycine to aspartic acid at position 25 (B7) of the δchain, was demonstrated for both cases. This is the second example of identification of δchain anomaly and includes the second and third examples of homozygosity for an abnormal hemoglobin among Japanese.

Abnormal hemoglobin

Hemoglobin A2