Background: This study was undertaken to analyse cases of microcytosis, and/or haemolytic anaemia where an unusual peak on HPLC or an abnormal electrophoretic mobility in isolation or along with common beta-globin gene defects was found, and to identify the molecular abnormality in them.
Patients and methods: Investigations included a complete blood count, HPLC analysis, cellulose acetate electrophoresis (pH 8.9), heat stability test and DNA sequencing.
Results: Five alpha chain variants were identified. This is the first report of Hb Jackson and Hb O Indonesia in the Indian population. The presence of Hb J Meerut along with Hb E and Hb J Paris I with heterozygous beta-thalassaemia are uncommon associations. Hb Sun Prairie would have remained undetected in the heterozygous state. The presence of a homozygous child in the family helped to identify this variant.
Conclusions: This study emphasizes the need to undertake systematic investigations while screening for the beta haemoglobinopathies to identify rare alpha chain variants in a population.