Molecular and hematological characterization of hemoglobin Hope/hemoglobin E and hemoglobin Hope/alpha-thalassemia 2 in Thai patients

Lab Hematol. 2004;10(4):215-20. doi: 10.1532/lh96.04050.

Abstract

We report the hematological and molecular characterization of compound heterozygosity for hemoglobin (Hb) Hope/Hb E and double heterozygosity for Hb Hope/ alpha-thalassemia 2 found in 2 unrelated Thai individuals. The first proband presented with slight anemia and mild hypochromic microcytosis. Routine cellulose acetate Hb electrophoresis at pH 8.6 revealed in addition to Hb E another variant migrating slightly more anodic to Hb A. On cation exchange high-pressure liquid chromatography, the variant was eluted in the amount of 60.9% after Hb E The same abnormal Hb was found in a second family in which the proband and her younger sister were both double heterozygotes for this Hb variant and deletional alpha-thalassemia 2, whereas an older sister was a pure carrier of the variant. The amounts of this variant were found to be 34.9%, 35.4%, and 38.3% in the proband, her younger sister, and her older sister, respectively. Direct DNA sequencing of the amplified beta-globin genes of both probands identified the GGT (Gly)-GAT (Asp) mutation at codon 136 corresponding to Hb Hope. beta-Globin gene haplotype analysis demonstrated that all the Thai betaHope genes were associated with the same haplotype, (+ - - - - + +), indicating a single origin of this variant in Thailand. A simple method based on allele-specific polymerase chain reaction for accurate diagnosis of the Hb Hope is described.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Chromatography, High Pressure Liquid
  • DNA Mutational Analysis
  • Electrophoresis
  • Family Health
  • Female
  • Haplotypes
  • Hemoglobin E / genetics*
  • Hemoglobinopathies / diagnosis*
  • Hemoglobins, Abnormal / genetics*
  • Heterozygote
  • Humans
  • Mutation, Missense
  • Pedigree
  • Pregnancy
  • Thailand
  • alpha-Thalassemia / genetics*

Substances

  • Hemoglobins, Abnormal
  • Hemoglobin E
  • hemoglobin Hope