Targeted correction of the point mutations of beta-thalassemia and targeted mutagenesis of the nucleotide associated with HPFH by RNA/DNA oligonucleotides: Potential for beta-thalassemia gene therapy

An RNA/DNA chimeric oligonucleotide was found to be effective in the target ed correction of point mutations in Escherichia coli, plant, and mammalian genomes. This strategy, named chimeraplasty, has the potential for gene the rapy of many genetic diseases caused by point mutations. beta -Thalassemia is a very common human genetic disease and in most cases it is caused by po int mutations. To lest whether the chimeraplasty can be used to correct the point mutations responsible for beta -thalassemia, we introduced one mutat ed beta -globin gene, betaE, into MEL cells and successfully corrected the point mutation of the betaE gene with the highest correction efficiency of 1.9%. Furthermore, a targeted -202C -->G mutation of the G gamma -globin ge ne, which is associated with the elevated C gamma -globin gene expression i n the adult stage, was introduced into HeLa and CMK cells by an RNA/DNA oli gonucleotide. These results indicated that the chimeraplasty has potential for human beta -thalassemia gene therapy. (C) 2001 Academic Press.