A further case of beta -thalassemia with an homozygous T arrow right C substitution at the donor splice site of the first intervening sequence of the beta -globin gene

Several point mutations occurring in the junction region between the first exon and the small intervening sequence (IVS-I) of the beta -globin gene have been described. The mutations create the integration of IVS-I sequences in primary transcripts of the beta -globin gene and are responsible for different forms of beta -thalassemia. We describe a patient with thalassemia intermedia who is homozygous for the T arrow right C substitution at the GT splicing signal in the first IVS of the beta -globin gene (IVS-I-2 T arrow right C). This mutation has been found in a Black patient living in North America. (DBO)