Distribution of haptoglobin phenotypes in a Korean population, using the semi-automated PhastSystem

Abstract

We have established a new phenotyping method for haptoglobin, based on sodium dodecyl sulphate-polyacrylamide gel electrophoresis using the PhastSystem (Pharmacia Biotech, Uppsala, Sweden), followed by immunoblotting for detection. We measured haptoglobin concentrations and determined the haptoglobin phenotypes of 316 healthy Koreans using this method: 31 (9.8%) were of Hp 1-1 type, 140 (44.3%) of Hp 2-1 type and 145 (45.9%) of Hp 2-2 type. The haptoglobin allele frequencies were calculated to be 0.32 for Hp1 and 0.68 for Hp2. We were able to visualize up to 12 bands from the human Hp 2-2 polymeric series, with molecular weights in the range 171.9 x 10(3) to 802.2 x 10(3). The reference range of serum haptoglobin concentrations obtained by the IFCC (International Federation of Clinical Chemistry) standard method was 0.27-2.14 g/L. The serum haptoglobin concentration in Koreans was similar to that of Caucasians, but the Hp1 allele frequency was lower in Koreans. Our method could be used in clinical laboratories as a simple and practical method of haptoglobin phenotyping. In addition, the Hp 2-2 polymeric series could be used as high molecular weight standards.