ALBERT

Description: By means of fractional denaturation, it is possible to follow the progress of alkaline degradation of resistant hemoglobins. A characteristic pattern was established for the fetal compound. The alkali resistant hemoglobin fractions in Mediterranean anemia and in some acquired hematologic conditions (acute leukemia and chronic aregenerative anemia) behaved like the fetal pigment. In sickle cell anemia only 4 out of 11 specimens were found to have fetal hemoglobin, whereas the others seem to have a fetal-like compound. Similarly, in 2 members of one family with hereditary spherocytosis, the resistant pigment was also fetal-like. The significance of these findings for the hypothesis that the resistant hemoglobin fractions in these disorders represent either a continuation or a reactivation of the production of the embryonic pigment is discussed.

Description: 1. A Negro family is described in which several individuals exhibit either the manifestations of thalassemia, or of the uncomplicated hemoglobin C trait; in two members the combined occurrence of these two anomalies is demonstrable. This combination is designated as hemoglobin C—thalassemia disease. 2. Hemoglobin C—thalassemia disease manifests itself in these two patients as a microcytic erythrocytosis. The red cells reveal a low MCV and low MCH, but a normal MCHC. About 45 per cent of the erythrocytes appear as target cells in the film. The amount of hemoglobin C in the hemolysates was about 75 per cent, the remainder being composed of A hemoglobin, and in one instance also of a small quantity of F hemoglobin. This is analogous to the results of the hemoglobin analyses in sickle cell—thalassemia disease, where 60 to 80 per cent of the pathologic hemoglobin S are found, though these individuals are heterozygous for both the pathologic hemoglobin and the thalassemia genes. The hypothesis is advanced that the thalassemia gene modifies (enhances) the expressivity of the gene for the pathologic pigment. 3. In genetic studies of families with thalassemia, hemoglobin analyses represent a necessary requirement. It is now established that thalassemia, as well as disorders associated with hemoglobin C, reveals a tendency to leptocytosis and thus may show erythrocytes with increased osmotic resistance. 4. The segregation of the thalassemia gene and of the genes for pathologic hemoglobins take place independently of each other. These genes are not allelomorphs.

Description: 1. When sufficiently concentrated sickle cell hemoglobin containing solutions are exposed to a constant stream of CO2 gas, the hemolysates gel. This gelling phenomenon is indicative of the presence of S hemoglobin and cannot be obtained with any other type of human hemoglobin in the absence of S pigment. The lowest S hemoglobin concentration (Gm. per cent) of a hemolysate at which the gelling phenomenon can still be elicited is designated as its lowest gelling point. 2. A simple apparatus was developed to analyze the gelling phenomenon under standardized conditions. It could be shown that the lowest gelling points of hemolysates prepared from erythrocytes of the sickle cell trait (containing A + S hemoglobins), of the "C variant" (containing C + S hemoglobins), and from sickle cell anemia cells (containing S + F hemoglobins) differ distinctly. Further experiments suggest that the presence of A hemoglobin decreases the minimal amount of S pigment required for gel formation, and that type C hemoglobin reduces this amount even further. F hemoglobin seems to exert no significant influence on the gelling phenomenon. Serum albumin is also capable of decreasing the amount of S hemoglobin required for gelation. 3. A sickled erythrocyte is visualized as an S hemoglobin tactoid or gel, specifically influenced by the companion pigment which interacts with the S compound. Thus, in the sickle cell trait, a positive sickling test is not only caused by the presence of S hemoglobin, but also by its interaction with A hemoglobin. Only in the sickle cell anemia cells does sickling seem to depend solely upon the interaction of the S hemoglobin molecules. 4. The readily demonstrable differences of the lowest gelling points of hemolysates prepared from the various types of sickling red cells form the basis of the diagnostic gelling test which distinguishes sharply between sickle cell anemia and sickle cell trait erythrocytes. By this procedure atypical cases of sickle cell disease, for example, those whose erythrocytes contain C hemoglobin, may also be detected.

Description: The results of starch block electrophoresis of normal adult hemoglobin in the various disease states has been reported. The slow-moving fraction, A2, is elevated in all patients so far studied with thalassemia. Some patients with Addisonian pernicious anemia also show an increase in this fraction. Cord blood contains very little A2. The A2 fraction has no correlation with the severity of the disease. The A2 fraction found on starch seems to be identical with the small, fast-moving component noted in the Tiselius apparatus at acid pH. Iron deficiency anemia of the acquired type tends to have a lower amount of A2 than normal, with an increase to average normal values after therapy.

Description: A family study is reported in which the simultaneous presence of C-thalassemia and S-thalassemia disease is noted. Marked interaction of the genes for the abnormal hemoglobins and for thalassemia is evident. The value of the accessory hemoglobins for the diagnosis of thalassemia minor is discussed. The Hb S + F pattern can no longer be assumed to be diagnostic of sickle cell anemia. Evaluation of all hematologic data and the family background of the patient may be necessary to rule out the presence of the thalassemia gene. A discussion of the genetics of the double heterozygous states for thalassemia and an abnormal hemoglobin is presented.

Description: (1) Four Negro patients with mild sickle cell-thalassemia disease (heterozygous for the genes for S hemoglobin and for thalassemia) are described. In contrast to reports in the literature, some of these patients are only mildly anemic, or not anemic at all. In three, the values for MCV and MCH are decreased, but in one, all hematologic indices are normal. All four individuals show leptocytosis and elevated reticulocyte levels. (2) Hemoglobin analyses, consisting of a combination of electrophoresis and the alkali denaturation technic, demonstrate the S + A + F pattern in three, and the S + A pattern in the fourth. These patterns are considered pathognomonic for sickle cell-thalassemia disease. They may be sharply differentiated from the S + F pattern, encountered in classical (homozygous) sickle cell anemia, and from the A + S pattern found in the heterozygous sickle cell trait. The various types of hemoglobin are reported in the sequence of their quantitative representation in the hemolysate. Hemoglobin analysis is indispensable for the recognition of the different types of sickle cell disease. (3) Evidence is cited that clinically almost asymptomatic sickle cell-thalassemia disease is probably not too rare in the American Negro population. (4) The genetic aspects of the production of fetal hemoglobin are discussed. It is postulated that the production of fetal hemoglobin is also under genetic control. The genes for fetal hemoglobin are not alleles of the genes for normal adult hemoglobin and are physiologically almost completely suppressed by the latter. Pathologic genes may render this suppression incomplete.

Description: 1. By exposing hemoglobin solutions to an alkaline reagent at a pH of 12.7 it was found that normal pigment is completely denatured within one minute. Thus even small amounts of more resistant hemoglobins, which may also be present in the solution, can be readily detected. Fetal hemoglobin, which is alkali resistant, may remain demonstrable until the end of the second year of life. 2. Alkali resistant hemoglobins were regularly encountered in sickle cell anemia (but not in the trait), in the more fully developed Mediterranean syndromes, and in 1 out of 4 families with hereditary spherocytosis. In addition to these hereditary hemolytic disorders, abnormally denaturing hemoglobin fractions were observed in 3 instances of chronic aregenerative anemia, and, irregularly, in patients with untreated pernicious anemia, acute and chronic leukemia and myelophthisic anemia. All other kinds of anemias were found to have only normally denaturing pigments. 3. Three definite types of hemoglobin are identifiable at present by means of electrophoresis and denaturation. These have been designated as type N (normal adult), type F (fetal), and type S (sickle cell hemoglobin). The hypothesis is advanced that the resistant fraction in the hereditary hemolytic syndromes may represent a continued production of fetal pigment beyond the physiologic age limit and the appearance of the abnormal hemoglobins in the "acquired" disorders may indicate a reactivation of such a mechanism. The implications of such an assumption for the distribution of the various types of hemoglobin in sickling erythrocytes are discussed. 4. The diagnostic significance of the denaturation test and its limitations are outlined.