In the present investigation we did not observe age or sex differentials in the prevalence of sickle cell or HbC-traits in Black males or females of low socioeconomic status. When our data were compared to those of others, we found no evidence for a socioeconomic differential in the prevalence of these traits.

We present comparative results of three diagnostic tests for identification of hemoglobin S, performed on specimens from a total of 4,739 persons. A simple, rapid, and economical procedure for cellulose acetate electrophoresis was more efficient than either the "Sickledex" test (a dithionite test) or the metabisulfite reduction test. This is an important consideration as a minimum requirement for effective therapy and genetic counseling. We propose electrophoresis of hemoglobin on cellulose acetate as a primary screening procedure—with verification of positive samples by solubility tests—and discuss its feasibility.

We compare and discuss three electrophoretic methods for identifying hemoglobins S, A, C, F, and D or G. Electrophoresis on citrate agar gel was more sensitive than electrophoresis on cellulose acetate for detecting hemoglobins S and F, a fundamental consideration in designing cord-blood screening programs for detecting hemoglobin S carriers. Electrophoresis on starch gel is evidently an acceptable method for subtyping hemoglobins AA, CC, AS, SS, AC, and SC, and is more sensitive than cellulose acetate for identifying hemoglobin A1A2. Costs for the citrate agar gel, cellulose acetate, and starch gel procedures are presented.