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We describe a method of electrophoresis of hemoglobin on cellulose acetate plates impregnated with citrate agar, which remain stable for many months and are used to confirm rapidly the presence of hemoglobins S and C and the hemoglobinopathies associated with them. The method also provides excellent separations of hemoglobins F and A and reliable identification of genetically determined hemoglobin abnormalities in the newborn.

A new hemoglobin variant found in a mother and her child was characterized by column chromatography of the tryptic hydrolysate of the aminoethylated, glycinamidated beta-chain, followed by chymotryptic digestion of the abnormal beta T-9 peptide and amino acid analyses. It was shown to be alpha2beta2 73(E17)Asp replaced by Val and named by Hb Mobile.

Hemolysates of erythrocytes from more than a quarter million people in Alabama were electrophoresed on cellulose acetate, pH 8.4, and those samples exhibiting an abnormality were also electrophoresed in citrate agar, pH 6.0. The globin chains of mutants other than Hb S and C were electrophoresed in urea-mercaptoethanol buffers at both pH 8.9 and pH 6.0, and 60 of them were also analyzed structurally. Of about 6000 samples from whites, only three contained abnormal hemoglobins--Hb D Los Angeles, Hb J Baltimore, and one unidentified. Of 249,000 samples from blacks, about 29,000 contained electrophoretically detectable abnormalities, most of them associated with Hb S or C, present in a frequency of about 9% and 3%, respectively. About 1000 samples resolved into patterns of potential clinical significance. Twenty other mutant hemoglobins were detected, in various genetic combinations in 164 kindreds; four of these-Hb Alabama, Montgomery, Titusville, and Mobile-- were previously unknown. The methods used are rapid, economical, and well suited for large scale surveys. They provide highly specific characterizations of many mutant hemoglobins, and no discrepancies were found between the presumptive identifications based on these characterizations and the definitive identifications obtained from structural analyses.