Expression of a β thalassemi gene with abnormal splicing

Abstract

Expression of a cloned human β thalassemia gene with a single base change at position 5 of TVS 1 has been analyzed 48 hours after transfer of the gene into Hela cells (transient expression). Little or no normal β globin mRNA accumulates in the presence of the abnormal β gene in contrast to significantly more normal β mRNA produced with other mutations at this same position. By contrast, large amounts of an abnormal β globin mRNA are present; this is due to the use of a cryptic 5' splice site in exon 1 rather than the normal 5' splice site of IVS 1. The results indicate the variability of the effect on RNA splicing of different single base defects within IVS.