IN-VIVO SITE-DIRECTED MUTAGENESIS OF THE FACTOR-IX GENE BY CHIMERIC RNA DNA OLIGONUCLEOTIDES/

A chimeric RNA/DNA oligonucleotide was constructed to induce a sequenc e mutation in the rat factor IX gene, resulting in prolonged coagulati on. Oligonucleotides were targeted to hepatocytes in cell culture or i n vivo by intravenous injection. Nucleotide conversion was both site-s pecific and dose-dependent. The mutated gene was associated in vivo wi th significantly reduced factor IX coagulant activity and a marked pro longation of the activated partial thromboplastin time. The results de monstrate that single base-pair alterations can be introduced in hepat ocytes in situ by RNA/DNA oligonucleotides, suggesting a potentially p owerful strategy for hepatic gene repair without the use of viral vect ors.