Abstract
A minor hemoglobin (Hb) component with the electrophoretic properties of the delta-chain variant Hb A(2') was encountered in two unrelated families of Russian-Jewish ancestry. This minor component, designated Hb NYU, was shown to result from the substitution of lysine for asparagine at delta(12). We have confirmed studies of others that hemoglobin A(2') isolated from the hemoglobin of some African subjects, results from the replacement of the normal glycine at delta(16) by arginine. Thus for interpretations of the incidence of delta-chain variants in different populations, electrophoretic data are not sufficient. In members of one of the families in the present study, the visual estimations of normal Hb A(2) and of Hb NYU on starch-gel electrophoretic patterns suggested the presence of delta-thalassemia. In hemolysates of one of the heterozygotes for Hb NYU, hemoglobin A(2) was not demonstrable with starch-gel electrophoretic methods but was readily recovered by column chromatography in approximately the amounts expected for delta-chain heterozygotes.