The spectrum of beta-thalassaemia in Burma.

The molecular defects causing beta-thalassaemia (beta-thal) have been analyzed in 63 unrelated Burmese patients. The patients include 49 with Hb E/beta-thal, 13 with beta-thal major and 1 with Hb S/beta-thal. Using synthetic oligonucleotide probes and aided by the polymerase chain reaction 64/76 (84%) of the alleles have been characterized. To date 6 mutations have been identified. The most common mutation is the splicing defect at IVS-1 nt 1 which accounts for 32% of the alleles. Complete characterization of these alleles should aid the initiation of a prenatal diagnosis programme for beta-thalassaemia in the Burmese population.