Hemoglobin H associated with an uncommon variant of thalassemia trait.

I N 1955 RIGAS ET AL.1 and Gouttas et al.2 independently reported the discovery of a new hemoglobin characterized electrophoretically at pH 8.6 by a more rapid anodal mobility than that of normal adult hemoglobin. This hemoglobin has subsequently been identified by the letter “H.” More recently, “fast” hemoglobins other than “H” have been described. These include hemoglobins J,3 J,4-1#{176} K,5 -13 N’3 and two others found in infants but not identified by letters.13”4 The anodal migration rate of hemoglobin H, on paper electrophoresis at pH 8.6, is distinct from all others except hemoglobin I. At pH 6.5 the anodal migration of hemoglobin H distinguishes it from hemoglobin I. The spontaneous denaturation of hemoglobin I-I within intact erythrocytes in vitro, results in the formation of multiple inclusion bodies. This process, which is accelerated by the incubation of red cells at 37 C. with brillant cresyl blue, or with the reducing agent, sodium dithionite, results in a characteristic appearance which is sufficient to enable detection of the anomaly.2 The familial transmission of most abnormal hemoglobins has been illustrated by the demonstration of the hemoglobin in question in at least one parent of the propositus if adequate family studies were performed. The inheritance of hemoglobin H differs from this pattern. Apparently, hemoglobin H is only manifest if accompanied in the same individual by another genetic anomaly pertaining to hemoglobin formation. Thus, it has been demonstrated only when associated with thalassemia (or similar) trait, except for one instance and in that case it was associated with a new abnormal hemoglobin identified as by Vella et al.15 In some instances, therefore, hemoglobin H has been inherited from a parent in whom the presence of the abnormal hemoglobin could not be demonstrated. The occurrence of hemoglobin H in a 26 year old American woman of Sardinian descent is reported in this paper. In this instance the associated “thalassemia trait” in relatives was unusual because of the absence of the characteristic elevation of the A2 component.