Hyperunstable hemoglobin koriyama found in a Japanese girl with severe hemolytic anemia : Tandem insertion of 5 residues in cluding the proximal histidine in the β chain

A hyperunstable hemoglobin, Hb Koriyama, was discovered in a 17-years-old Japanese female suffering from asevere chronic hemolytic anemia. The abnormal hemoglobin formed a barely perceptible minor band between Hb A and Hb F in isoelectric forcusing of the hemolysate.The abnormal β chain emerged as a minor peak with very high specific activity between the normal β and δ chain in CM-cellulose olumn　chromatography of the ^3H-leucine-labeled globin.　It was S-acetamidated and digested with a protease from staphylococcus aureus V_8. Reverse phase high performance liquid chromatography of the digest revealed an abnormal fragment. Amino acid analysis and Edman degradation of the abnormal V_8 peptide established that a segment consisiting of five residues (either Leu-His-Cys-Asp-Lys, His-Cys-Asp-Lys-Leu or Cys-Asp-Lys-Lue-His) was repeated in tendem. The parents and siblings of the proposita were hematologically normal.