Molecular analysis of a Thai β-thalassaemia heterozygote with normal haemoglobin A2 level: implication for population screening

摘要: BACKGROUND This study aimed to characterize the molecular basis of a beta-thalassaemia heterozygote who had normal haemoglobin A2 level. METHODS Using haematological and analyses, alpha- beta-globin genotypes in Thai woman with level, was identified thalassaemia haemoglobinopathy screening programme, were examined. RESULTS The patient positive for 0.36% one-tube osmotic fragility test but negative dichlorophenolindophenol dye E. Haemoglobin A observed on cellulose acetate electrophoresis 2.0%, compatible an alpha-thalassaemia 1 carrier. Polymerase chain reaction analysis failed detect (South East Asian deletion). Beta-globin gene detected severe betao-thalassaemia allele 4 bp (-CTTT) deletion at codons 41/42. Further alpha-globin homozygosity 3.7 kb 2. CONCLUSIONS found be unusual case: carrier low concentration, combination 2 deletion. approach used result obtained this report will prove useful population regions where both beta-thalassaemias are common.