Restriction endonuclease mapping of globin genes in beta-thalassaemia.

We have used the restriction endonuclease mapping technique to analyse the globin genes in local cases of beta-thalassaemia major. No gross deletions or rearrangements of the beta-globin gene locus were detected. In one individual the point mutation within the beta-globin gene which gives rise to a beta(0)-thalassaemia allele was detected by use of a restriction enzyme which cuts the gene at this site. Analysis of restriction fragment length polymorphisms at the beta-globin locus showed that antenatal diagnosis of the disorder could be accomplished in an indigenous family with thalassaemia. The application of the gene-mapping technique to the diagnosis of sickle cell anaemia and alpha-thalassaemia is also discussed.