A beta-thalassaemia allele with 3 base substitution in codons 4/5 & 6 (ACT CCT GAG-> ACA TCT TAG) detected by denaturing gradient gel electrophoresis & sequencing.

We report the analysis of a beta-thalassaemia gene involving three bases in codons 4/5 and 6 (ACT CCT GAG-> ACA TCT TAG) in a confirmed carrier whose child had beta-thalassaemia major. The fragment of the gene carrying the mutation was detected by denaturing gradient gel electrophoresis (DGGE) using GC clamped primers, followed by direct sequencing. DGGE analysis indicated that one gene was the wild type (normal) while the sequence changes observed were all in the other gene causing beta-thalassaemia major in the child. This confirms a single case report from Lucknow (UP) and adds to the beta-thalassaemia mutations identified in the beta-globin gene in India and will help in the thalassaemia control programme.