BACKBONE MODIFICATIONS IN OLIGONUCLEOTIDES AND PEPTIDE NUCLEIC-ACID SYSTEMS

In the past year major advances have been made in the design, synthesi s and characterization of two classes of modified oligonucleotides. In the first class, the phosphodiester backbone of 2'-deoxyribo-oligonuc leotides has been replaced in several different ways. The second group represents a completely different type of oligonucleotide modificatio n in which the backbone and the 2'-deoxyribose moieties are replaced b y amino acids. These advances present new possibilities for the pharma ceutical applications of modified oligonucleotides in antisense strate gies.