Molecular analysis of beta-thalassemia in Vietnam.

The molecular basis of the thalassemias has been studied in many of the world's populations. Here we report the results of the first screening for mutations in Vietnam. Twenty-three unrelated patients, of which 17 have Hb E/beta-thalassemia, were diagnosed and beta-globin mutations were detected in all 46 chromosomes. Four previously reported South Asian mutations were found. The most common mutations were the nonsense in codon 17 (A-->T) and the frameshift at codons 41/42 (-TTCT) (30 and 22%, respectively). The rare frameshift mutation at codon 95 (+A) was present in 9% of the 46 chromosomes studied, suggesting that it is indigenous to Vietnam. These results will serve as an initial database for DNA-based prenatal diagnosis of thalassemia in Vietnam.