title: Hb Q-India: an uncommon variant diagnosed in three Punjabi patients with diabetes is identified by a novel DNA analysis test.
abstract: OBJECTIVE
  An abnormality in the glycated haemoglobin peak (Hb A1c) on Diastat (Bio-Rad) cation exchange low pressure liquid chromatography (LPLC) was found in three Punjabi patients with diabetes. The aims of this study were to identify the variant by chromatography and electrophoresis and to determine whether a DNA analysis test could be designed for confirmation that could be generally applied for the identification of any unusual abnormal haemoglobin.
  
  
  METHODS
  The presence of an Hb variant was confirmed by cellulose acetate electrophoresis at pH 8.6. The variant was characterised further by high performance liquid chromatography (HPLC; Bio-Rad Variant) and isolelectric focusing (IEF) electrophoresis. A novel DNA analysis test based on the amplification refractory mutation system (ARMS) and the polymerase chain reaction (PCR) was developed to confirm the presence of the mutation for the uncommon variant.
  
  
  RESULTS
  Comparison of the HPLC retention time and IEF band position determined the presence of the variant Hb Q-India in all three cases. Hb Q-India is caused by the mutation GAC --> CAC at codon 64 of the alpha-1 globin gene and is clinically silent. ARMS-PCR specific primers were designed and used successfully to confirm the presence of the mutation for Hb Q-India.
  
  
  CONCLUSIONS
  The results show that the ARMS-PCR technique, developed previously for the diagnosis of beta thalassaemia mutations, can also be adapted to provide a simple, rapid, and inexpensive approach for the identification of abnormal haemoglobins.
authors.affiliation: Department of Biochemistry, Christian Medical College and Hospital, Ludhiana, Punjab 141008, India.
authors.forename: R
authors.initials: R
authors.lastname: Abraham
authors.forename: M
authors.initials: M
authors.lastname: Thomas
authors.forename: R
authors.initials: R
authors.lastname: Britt
authors.forename: C
authors.initials: C
authors.lastname: Fisher
authors.forename: J
authors.initials: J
authors.lastname: Old
mesh_terms: D000328:Adult; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004252:DNA Mutational Analysis / Q000379:methods; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D006455:Hemoglobins, Abnormal / Q000032:analysis* / Q000235:genetics; D006801:Humans; D007525:Isoelectric Focusing; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction / Q000379:methods
chemical_list: D006455:Hemoglobins, Abnormal; C048600:hemoglobin Q India