Alan S. Jacobs

Haemoglobin New York

A haemoglobin variant has been found in which a glutamic acid amino-acid residue is substituted at position 113 in the β chain for the usual neutral valine. This haemoglobin is called after the city in which it was found and is Hb-β1 13 Glu.

Hemoglobin Riverdale-Bronx an unstable hemoglobin resulting from the substitution of arginine for glycine at helical residue B6 of the β polypeptide chain

Abstract Hemoglobin Riverdale-Bronx is a heat unstable hemoglobin isolated from the erythrocytes of a 45 year old woman of German-Jewish ancestry who had a fairly well compensated hemolytic anemia. Structural studies of this hemoglobin have revealed the substitution of arginine for the normally occurring glycine at helical residue B6 (β24) of the β polypeptide chains. According to Perutz, Kendrew and Watson, glycine B6 is an invariant non-polar residue, which is in close contact with E8, a glycine residue adjacent to the distal heme-linked histidine (E7). The replacement of the invariant non-polar glycine with arginine at this site would be expected to alter the relationships of the E-helix to the heme of the affected (β) polypeptide chains.

Hemoglobin NYU, a delta chain variant, α2δ212Lys

A minor hemoglobin (Hb) component with the electrophoretic properties of the δ-chain variant Hb A2′ 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 δ12. We have confirmed studies of others that hemoglobin A2′ isolated from the hemoglobin of some African subjects, results from the replacement of the normal glycine at δ16 by arginine. Thus for interpretations of the incidence of δ-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 A2 and of Hb NYU on starch-gel electrophoretic patterns suggested the presence of δ-thalassemia. In hemolysates of one of the heterozygotes for Hb NYU, hemoglobin A2 was not demonstrable with starch-gel electrophoretic methods but was readily recovered by column chromatography in approximately the amounts expected for δ-chain heterozygotes.