Five alpha globin chain variants identified during screening for haemoglobinopathies.

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.